Extra Thick Lemon Bars with Brown Sugar Shortbread Crust

lemon bars

Classic lemon bars are the George Clooney of the dessert table. The perfect guest, they’re welcome for all occasions and in all seasons. Of course, they’re a natural in spring, all nice and fresh and lemony; but they’re just as welcome in summer after a barbecue, or in autumn when thoughts turn to comfort foods like pot pies and stews, and they’re especially enjoyed in winter when our waistlines can’t bear the thought of one more heavy dessert, but… lemon bars? Oh yessirree, we can make room for a few bites of those. With an extra thick lemon curd filling and a buttery brown sugar shortbread base, these are the best lemon bars EVER.

Close up of a lemon bar with powdered sugar topping
A plate of bright lemony goodness

What makes these extra thick lemon bars the best ever?

Have you ever eaten store-bought lemon bars? They’re usually sweet with little to no tartness, and their crusts are usually a bit on the soggy side. At least that’s been my experience. Once I learned to make lemon bars from scratch, I never bought one again. It’s just not worth it.

Lemon bars are like bite-size versions of lemon meringue pie. They’re just as sweet-tart, but they’re small enough to enjoy without having to wait for dessert. They’re just perfect for that “bite of sweet” when pie might be a bit much.

What makes this easy lemon dessert so special is the crust. Most lemon bar recipes use white sugar, which makes a pale, shortbread crust. These easy lemon bars, however, have a secret ingredient – brown sugar – which gives the crust a wonderful buttery, brown sugar sweetness that blows the ordinary crusts out of the water. This crust comes out slightly crunchy, too, which is a bonus if you’re tired of the soggy crusts of typical lemon bars. Luckily the brown sugar doesn’t add extra sweetness to the already sweet confection – it just adds a lovely rich, mellow flavor.

In fact, this crust is so good you might even catch yourself eating the filling first and saving the crust for last as one in my family tends to do. (Yes, I’m talking about you, Mr. Right.)

The offset spatula is my best friend when making this crust. It packs the crust down lickety split in seconds without my fingers ever touching the mixture. And it gets in the corners and along the sides much better than my fingers ever could.

Add to that the thick lemon curd filling, which is made with only four ingredients: eggs, sugar, lemon juice and flour. These are the thickest lemon bars I’ve ever seen. Most lemon bars are rather on the thin and skimpy side, but these bars are a force to be reckoned with. They call for eight (yes, that’s 8) eggs which yield a firm, rich custard worthy of being called the best.

The best lemon bars call for fresh lemon juice

Let’s talk about the lemon juice. There is only one way to make these bars, and that’s using fresh lemon juice. Bottled just won’t give the same flavor, the same zing that fresh will. It’s not even a close comparison. Think My Little Pony compared to the Budweiser Clydesdales. Not even close. So spend the extra few minutes juicing the lemons. Besides, you need a little of the lemon zest to give the flavor an added lemony boost.

Here’s my favorite juicer (the updated version – mine is old as the hills) – it makes short work of juicing a lot of lemons. (In this case a LOT of tiny lemons.) It will save tons of time, plus your hands if they’re even slightly arthritic. Just sayin’.

Cuisinart juicer in the process of jucing lemons
My favorite tool for lemon desserts

Handy tip: If you bought more lemons than you need, juice them all (especially if you have that nifty juicer!). Lemon juice freezes beautifully so you won’t have to go to the trouble the next time you make these. Same with the zest – it freezes well, too.

And speaking of lemon zest, you do zest, right? If you have the right tool, it only takes a few seconds. Really. You can zest a whole lemon in 30 seconds or less with this microplane, which is also handy for zesting other citrus fruits too. Or chocolate, parmesan cheese, or coconut.

Close up of lemon zest and microplane
An important ingredient in lemon desserts

You’ve got questions, I’ve got answers

How do I know when lemon bars are fully cooked?

Lemon bar filling is lemon curd which, when baked, becomes a custard. And perfect custard can’t be tested the way you would a cake, by sticking a knife or skewer into the middle. It won’t come out clean, and you’ll risk over baking it. To test that it’s done, first check the edges of the bars. They should be just barely starting to turn golden. Not brown, just “baked.” Then give the pan a slight jiggle. If the filling is liquid and watery in the center, it’s not cooked enough. When it’s cooked through, the filling will have a “soft” wiggle to it, not a watery one. Think of jello when you jiggle it. That softness will continue to firm up enough for cutting when chilled.

My lemon bars are rubbery – what did I do wrong?

Custards, which lemon bars are, can misbehave when overcooked. Some custards separate and go all watery on you, but lemon bars will turn tough and rubbery. Keep an eye on your bars towards the end of the baking time, and use the “jiggle test” as described above to determine if they’re cooked enough.

How do I cut lemon bars cleanly?

I get it, you want your bars to look crisp and clean around the edges for guests (because, if it’s just for us, do we really care about messy edges?). The best way to do this is to have a bowl of warm water standing by, and a thin, sharp knife. Dip the knife in the water, wipe clean and cut. The slight warmth of the knife edge will give those bars a clean, tidy edge.

Should I refrigerate lemon bars?

The short answer is yes, lemon bars MUST be refrigerated. The filling is a custard, rich with eggs and sugar, both of which spoil at room temperature. Refrigerate your lemon bars, both for health reasons and also because they cut and taste better cold. Let them cool for one hour after baking (or to room temperature), cover them with plastic wrap, and then pop them in the fridge for 2 more hours. Then they’ll be ready to cut and eat.

(For a good, easy bar cookie that doesn’t need refrigeration, try these fudgy oatmeal cookie bars.)

Why are my lemon bars green? Ew!

Acidic ingredients, such as citrus juices and tomato juice, react with aluminum which discolors the mixture and gives off a metallic taste, which is why they should never be made in aluminum pans. Next time make your lemon bars in a glass, ceramic, or stainless steel pan. I’ve been using my stainless steel pan for 15 years with excellent results. It’s not as pretty as a glass pan, but I serve my lemon bars on pretty plates anyway.

Can I freeze lemon bars?

Lemon bars don’t freeze well, just like most custards. The filling can separate and become watery, and the crust can become soggy. Lemon bars are best made the day of serving, or the day before (with proper storage). Thank goodness they’re so easy to make! However, if you must freeze them, cut them into bars when cooled (without the powdered sugar topping), wrap individually in plastic wrap, then place them in a large ziploc bag or other freezer container. Thaw in the fridge and dust with powdered sugar before serving.

How long will lemon bars stay fresh?

Lemon bars can be stored up to a week in the fridge. The powdered sugar will soak in over time, so just sift a fresh layer over the bars when serving. Which is not a bad thing if these are a little too tart for some.

A few more tips for baking extra thick lemon bars

  • Roll the whole lemons firmly on the counter before juicing – this breaks the cell walls down, releasing more juice.
  • Save the powdered sugar dusting until just before serving as the bars will soak it up and appear to “weep” if left to sit. Which will require another dusting. Which might not be a bad thing if these are too tart for some.
  • Make sure lemon bars are completely room temperature before putting them into the fridge. This helps prevent a soggy crust.

And last, what is that white film on top?

Sometimes you’ll get a thin white layer on top of the lemon layer during baking. Don’t worry, it’s just air from the whisked eggs rising to the top during the baking process. There’s no taste, and it’ll be covered with powdered sugar when the bars are served. Kind of like putting makeup on your lemon bars.

Let’s make the best extra thick lemon bars EVER!

Close up of a lemon bar with powdered sugar topping

Extra Thick Lemon Bars with Brown Sugar Shortbread Crust

With the rich crunch of a brown sugar shortbread base, and an extra thick zesty lemon curd filling, these lemon bars truly are the BEST lemon bars ever!
5 from 1 vote
Prep Time 30 mins
Cook Time 40 mins
Cooling time 2 hrs
Total Time 3 hrs 10 mins
Course Dessert
Cuisine American
Servings 24 bars
Calories 150 kcal


  • 9 X 13" ungreased baking pan (there's enough fat in the crust to prevent sticking)


Shortbread Base

  • 3/4 cup unsalted butter
  • 2 cups all-purpose flour
  • 1/2 cup packed light brown sugar
  • 1/2 tsp salt

Lemon Filling

  • 8 large eggs
  • 3 cups granulated sugar
  • 1 1/2 cups fresh lemon juice
  • zest of one medium or large lemon
  • 2/3 cup all-purpose flour
  • hot shortbread base
  • 3 Tbsp. confectioners sugar


  • Preheat oven to 350°.
  • Cut butter into 1/2-inch pieces.
  • In a food processor, process all ingredients until mixture begins to form small lumps.
  • Sprinkle mixture in a 13x9x2-inch baking pan and press flat with a metal spatula.
  • Bake in middle of oven until golden, about 20 minutes. While shortbread is baking, prepare topping.

Lemon Filling

  • In a bowl, sift flour and sugar together.
  • In separate bowl, whisk eggs until combined well.
  • Stir in lemon juice and zest, then whisk in sugar/flour mixture.
  • Pour lemon mixture over hot shortbread.
  • Reduce oven heat to 300° and bake in middle of oven until set, about 35-40 minutes.
  • Cool completely in pan, then chill.
  • Cut into 24 bars. Dust with powdered sugar before serving.
  • Refrigerate leftovers. Dust again with powdered sugar (which absorbs into the filling with time.)
  • Store for 3-5 days (if they last that long).
Keyword brown sugar shortbread crust, extra thick lemon bars, homemade lemon bars, lemon bars

My fave tools

Close up of a lemon bar with powdered sugar topping

With this extra thick filling, lemon bars are easy enough to make this morning for a yummy snack this afternoon

Make sure to share your success on the G&B Facebook page! Happy baking!

More easy lemon recipes…

Magic Lemon Curd – the Foolproof Method
Moist & Tender Coconut Cake with Lemon Curd Filling
Easy Foolproof Lemon Meringue Pie

Pin me for later!

4 thoughts on “Extra Thick Lemon Bars with Brown Sugar Shortbread Crust”

  1. 5 stars
    I never leave comments on recipe but this recipe deserves a comment! I am an experienced baker who have tried many recipes and have been asked and have made desserts for many special events from weddings to banquets, graduations, showers, corporate events…. I would describe these lemon bars as WOW! BEST lemon bars ever! The brown sugar in the crust makes these over the top! The bars have a thick filling (exactly what I was looking for) and are tart and lemony! I had a favorite lemon bar recipe but was intrigued by the brown sugar that was called for in this crust. Excellent! This will now be my favorite lemon bar recipe!

    1. I’m thrilled that you’ve found a new favorite! I never tire of these bars and they’re always a hit at family gatherings. Thank you for your lovely comment!

  2. What should the consistency be when they come out of the oven

    1. The filling should be soft but not “wet jiggly.” You’ll know the difference when you try to jiggle the pan gently. They will firm up when cool. Cut them with a sharp knife for clean cuts.

Leave a Comment

Your email address will not be published.

Recipe Rating

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Scroll to Top