Brown Sugar Butter Bars
Buttery, caramel-like, and wonderfully gooey in the center, these Brown Sugar Butter Bars give you all the cozy flavor of classic butter tarts — but in an easy, slice-and-serve bar form. A tender, shortbread-style base holds a rich brown sugar filling that bakes up glossy on top and just set in the middle, so every bite is soft, chewy, and sweet.
This is the kind of dessert you reach for when you want something homemade but don’t have time for rolling pastry or making individual tarts. Everything bakes in one pan, the ingredients are pantry-friendly, and the bars slice beautifully once cooled. They work for holidays, bake sales, potlucks, or just a weekend treat with coffee.
You can keep them classic with just brown sugar and butter, or add chopped pecans, walnuts, or raisins for that traditional butter tart twist. Either way, they’re rich, nostalgic, and dangerously easy to make.
Ingredients for Brown Sugar Butter Bars
This recipe uses simple baking staples, but each one plays a part in getting that perfect texture — crumbly on the bottom, gooey on top.
- Unsalted butter – Softened for the crust, melted for the filling; gives the bars their rich, buttery base.
- All-purpose flour – Forms the structure of the crust so it can hold the soft filling.
- Salt – Just a pinch to balance out the sweetness.
- Brown sugar – Packed and generous; it’s what gives the filling that caramel flavor and chewy texture.
- Eggs – Bind the filling so it sets without becoming dry.
- Vanilla extract – Adds warmth and a bakery-style aroma.
- Baking powder – Helps the filling puff slightly as it bakes.
- Optional nuts or raisins – For texture and a nod to classic butter tarts.
Step-by-Step Brown Sugar Butter Bars
STEP 1 – Make and Bake the Crust
Preheat your oven to 350°F (175°C) and line an 8×8-inch baking pan with parchment paper, leaving some overhang so the bars lift out easily. In a bowl, mix together the softened butter, flour, and a pinch of salt until the mixture looks crumbly and evenly combined. Press this mixture firmly and evenly into the bottom of the prepared pan. Bake for 12–15 minutes, just until the edges turn lightly golden. You don’t want it too dark — it will bake again with the filling.
STEP 2 – Prepare the Brown Sugar Filling
While the crust is baking, whisk together the melted butter and packed brown sugar in a separate bowl until smooth and glossy. Add the eggs one at a time, whisking well after each so the mixture is fully combined. Stir in the vanilla, baking powder, and a pinch of salt. If you’re using pecans, walnuts, or raisins, fold them in now so they’re evenly distributed. The filling should be thick but pourable.
STEP 3 – Pour and Bake Again
Once the crust comes out of the oven, pour the brown sugar filling right over the hot crust and spread it to the corners with a spatula. Return the pan to the oven and bake for 20–25 minutes, or until the top is shiny and the center is set but still has a slight jiggle. It will firm up more as it cools, so don’t overbake.
STEP 4 – Cool and Slice
Let the bars cool completely in the pan on a rack. For the cleanest slices, pop the pan into the refrigerator for about 30 minutes once it’s room temperature. Use the parchment to lift the bars out, then cut into squares or rectangles. The edges will be slightly chewy, and the center will be perfectly gooey.
Can I Add Nuts or Raisins Like Traditional Butter Tarts?
Yes — adding ½ cup of chopped pecans, walnuts, or even raisins gives these bars more texture and makes them taste even more like old-fashioned butter tarts. Fold them into the filling right before pouring it over the crust. If you like lots of texture, a mix of nuts and raisins works beautifully.
Why Do My Bars Need to Cool Before Slicing?
The filling continues to set as it cools. If you slice while warm, the center can be too soft and may ooze out. Letting the bars cool — or briefly chilling them — helps the butter and sugar firm up, giving you neat, bakery-style squares with a defined crust and gooey top.
Can I Double the Recipe for a Crowd?
Absolutely. You can double all the ingredients and bake the bars in a 9×13-inch pan. Keep an eye on the baking time for the second bake — it may need a couple of extra minutes, but don’t overbake or you’ll lose that soft, caramel center.
Helpful Tips
- Use parchment paper so the bars lift out easily and don’t stick.
- Measure the brown sugar packed to get the right chewy texture.
- Don’t overbake — the center should look set but not dry.
Serving Ideas for Brown Sugar Butter Bars
Serve these bars just as they are with coffee or tea, or warm them slightly and add a scoop of vanilla ice cream for a simple dessert. They also make a great addition to a dessert tray with brownies and lemon bars since they bring that caramel, buttery flavor to the mix.
Storage & Reheating
Store the bars in an airtight container at room temperature for up to 3 days, or refrigerate for up to 5 days if your kitchen is warm. They also freeze well — wrap tightly and freeze for up to 2 months. Thaw at room temperature and enjoy; no reheating needed unless you like them warm.
Brown Sugar Butter Bars
Ingredients
Base Layer:
- 1 cup plain flour sifted
- A generous pinch of fine salt
- ½ cup unsalted butter brought to room temperature
Caramel Filling:
- 2 large eggs
- ½ cup unsalted butter liquefied and slightly cooled
- 1½ cups packed soft brown sugar
- 1 teaspoon pure vanilla essence
- A small pinch of salt
- ½ teaspoon leavening powder
- Optional mix-ins: ½ cup chopped walnuts pecans, or dried raisins
Instructions
- Preheat your oven to 350°F (175°C) and prepare an 8-by-8-inch square baking tin by lining it with parchment paper, allowing the sides to hang over for easy removal.
- In a bowl, blend the room-temperature butter with the flour and salt using a fork or pastry cutter until the mixture forms coarse crumbs. Press this dough firmly and evenly across the bottom of the prepared pan. Transfer to the oven and bake for approximately 12 to 15 minutes, or until the outer edges begin to lightly brown.
- While the crust is baking, combine the melted butter with the brown sugar in a separate bowl, whisking until fully integrated. Incorporate the eggs, vanilla extract, baking powder, and salt into the mixture. Stir until smooth and cohesive. If using, gently fold in chopped nuts or dried fruit at this stage.
- Once the crust has par-baked, pour the prepared filling over it and smooth the top with a spatula. Return the pan to the oven and continue baking for 20 to 25 minutes, or until the filling is set in the center but retains a soft, tender texture.
- Allow the bars to cool completely in the pan. For cleaner slices, refrigerate for 30 minutes before cutting into portions.