These chewy, fudgy biscoff blondies showcase the warm caramel notes of Belgian speculoos cookies and creamy cookie butter. Cinnamon and nutmeg from the spread combine with brown sugar and butter for rich, warmly spiced bars. This easy one‑bowl recipe uses melted butter, so it comes together quickly by hand.
I always keep a jar of biscoff cookie butter in the pantry. After testing other blondie variations, it was obvious that the deep caramel flavor of Belgian speculoos cookies—and the cookie butter made from them—would pair beautifully with a buttery, brown sugar blondie base.
This recipe layers biscoff flavor throughout: crumbled cookies are folded into the dough, chunks are pressed into the top, and a swirl or drizzle of cookie butter finishes the bars. The result is a tender, fudgy blondie with plenty of spice and crunch.
If you love these flavors, try them in other forms as well, such as biscoff butter cookies or other bar cookie recipes.
[feast_advanced_jump_to]
Ingredients
* See the recipe card below for full measurements and details.
Unsalted butter – Melted butter makes this recipe easy to mix by hand and gives the bars a chewy, dense texture.
Cookie butter – Use creamy speculoos or Biscoff cookie butter. Either brand works well and contributes the signature caramel‑spice flavor.
Egg yolks – Using only yolks adds richness and reduces extra moisture, creating a fudgier blondie than whole eggs would.
Biscoff cookies – Chopped or broken pieces of speculoos cookies add crunch and texture inside the bars and on top as a finishing touch.
Instructions
Photos below illustrate the steps. Full step‑by‑step directions and quantities are in the recipe card.
Melt the butter with the brown sugar, whisking until smooth and glossy, then add the cookie butter and whisk to combine.
Whisk in the egg yolks, vanilla and salt until fully incorporated.
Stir in the flour with a spoon or spatula until just combined.
Fold in broken biscoff cookies so they are distributed through the batter.
Mix just until the cookies are evenly distributed to avoid overworking the batter.
Transfer the batter to a lined 8-inch (20 cm) square pan, press evenly into the corners, and press larger cookie pieces into the top.
Bake until set and golden at the edges, about 21–24 minutes. Cool on a wire rack. Warm a small amount of cookie butter until pourable and drizzle over the bars. Let cool completely before slicing.
For the cleanest slices and a fudgier texture, wait until the bars are completely cool before cutting. Cooling allows the butter and cookie butter to firm up.
Variations
The recipe highlights biscoff flavor as the star, but you can customize the bars to your taste:
- White chocolate: Fold in about 120 g (4 oz) coarsely chopped white chocolate or chips for contrast; you may need a few extra minutes of baking time.
- Extra spice: Add 1 teaspoon cinnamon and 1/4 teaspoon nutmeg to enhance the speculoos character.
- Chocolate chips: Stir in about 113 g (4 oz) semisweet or milk chocolate chips for a chocolatey twist; adjust bake time slightly if needed.
Equipment
8-inch square metal pan — A metal pan produces even baking and slightly crisp edges. If using glass, reduce oven temperature by 25°F and extend bake time a few minutes to avoid overbaked edges.
Different pan materials affect baking: metal heats quickly for crisper edges, while glass heats and retains heat more slowly, which can change timing and edge texture.
Storage
Store: Keep cooled bars in an airtight container at room temperature for up to a week.
Freeze: Freeze in an airtight container or zipped bag with parchment between layers for 2–3 months.
Recipe tip
If you work quickly while the butter is hot, the batter will be thinner; if it cools, the batter will thicken and need pressing into the pan. Both approaches produce excellent results—just press evenly before baking if the batter firms up.
Frequently asked questions
Cookie butter (also called speculoos or Biscoff spread) is a smooth paste made from ground speculoos cookies, oil, sugar and seasonings. It has a spreadable consistency similar to nut butter and comes in creamy and crunchy varieties.
Speculaas (or speculaas) are Dutch spiced cookies with a mix of warm spices such as cinnamon, nutmeg, cardamom and cloves. Speculoos are Belgian and typically use fewer spices—often just cinnamon—with a stronger caramelized brown sugar flavor. Biscoff is a well‑known brand of Belgian speculoos cookies.
Love this recipe? Please
leave a comment and star rating.
★★★★★ Your feedback helps other bakers!
📖 Recipe
Biscoff Blondies
INGREDIENTS
Biscoff Blondies
- 113 grams unsalted butter
- 175 grams brown sugar
- 90 grams cookie butter, creamy
- 2 large egg yolks
- 5 mL vanilla extract
- ½ teaspoon kosher salt
- 150 grams all‑purpose flour
- 4 biscoff cookies, broken into small pieces
Biscoff Blondie Topping
- 2 biscoff cookies, broken into larger pieces
- 30 grams cookie butter, warmed for drizzling
INSTRUCTIONS
- Place a rack in the center of the oven and preheat to 350°F (177°C).
- Line an 8-inch square metal pan with parchment, leaving an overhang for lifting the bars out.
- In a microwave‑safe bowl, heat the butter and brown sugar in 30‑second bursts until fully melted (about 60–90 seconds). Whisk until smooth and glossy. Add the cookie butter and whisk to combine. If it looks slightly curdled, the next additions will smooth it out.
- Whisk in the egg yolks, vanilla and salt. Stir in the flour until just combined.
- Fold in the 4 broken biscoff cookies, mixing only until distributed.
- Scoop the batter into the prepared pan and press evenly into the corners. Press the larger pieces from the remaining 2 cookies into the top.
- Bake for 21–23 minutes, until the center is set, the top is golden, and the edges pull away slightly from the pan.
- Let cool briefly, then warm the remaining 30 g (about 2 tablespoons) of cookie butter until pourable. Drizzle over the bars. Cool completely before slicing for neat squares.
NOTES
Batter consistency:
- If the butter is hot when you mix, the batter will be thinner; if the butter cools, the batter will thicken and need pressing into the pan—both deliver good results.
Slicing:
- Wait until the bars are completely cool for tidy, fudgy slices.
Storage:
- Store cooled bars in an airtight container at room temperature for up to a week.
- Freeze in an airtight container or sealed bag with parchment between layers for 2–3 months.
More bar cookies
-
Brownie Blondies
-
Raspberry White Chocolate Blondies
-
Caramel Pecan Shortbread Bars
-
German Cookies
This post was originally published June 22, 2022 and has been updated with labeled ingredient images and step‑by‑step photos.