These chewy, fudgy biscoff blondies are full of the warming, golden caramel flavors of Belgian speculoos cookies and cookie butter spread. Notes of cinnamon and nutmeg from the cookie butter combine with rich, buttery brown sugar in these rich bars. This easy, one bowl recipe uses melted butter so it's easy to make by hand.
I keep a jar of biscoff cookie butter in the pantry, and use it frequently. After making my raspberry white chocolate blondies and brownie blondies, I knew the caramel flavors of Belgian biscoff cookies (also known as speculoos) and the cookie butter spread made from them, would be the perfect pairing with the buttery, brown sugar flavors of blondies.
I've packed in as much biscoff flavor as possible. There are crumbled biscoff cookies in the dough and cookie chunks studding the top of the bars. I've added cookie butter spread to the dough and as a decorative drizzle on top. There's no shortage of warm spice taste here.
If you're a fan of biscoff, you'll also love these chewy biscoff butter cookies, which have a similar flavor profile in drop cookie form.
Explore the entire collection of cookie recipes here.
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Ingredients
* See recipe card for full list of ingredients and quantities.
Unsalted butter - Melting the butter makes this recipe easy to make by hand and creates a more chewy, dense cookie.
Cookie butter- I use the creamy variety of cookie butter spread here. You can find Lotus biscoff cookie butter spread online or in stores. Trader Joe's sells their own version of the spread, which you can also use.
Egg yolks - Using egg yolks rather than whole eggs adds additional flavor and richness while reducing moisture, creating a fudgier texture.
Yes, you might consider it a hassle to use the egg yolks. I've tested the recipe multiple times with both 2 whole eggs and 1 egg + 1 yolk, and those versions creates a cakier, spongier bar that I don't enjoy.
Biscoff cookies - Adding broken up biscoff cookies (also known as speculoos cookies, or Belgian spice cookies) contributes additional texture, crunch and flavor.
You can buy Lotus Biscoff cookies online or find them in the cookie aisle in many grocery stores.
Instructions
These photos provide visual cues. Find detailed instructions in the recipe card.
Melt butter and brown sugar together in the microwave. Whisk until well incorporated. Add biscoff spread.
Add egg yolks, vanilla and salt, mixing thoroughly until fully incorporated.
With a spoon or spatula, mix in flour.
Break 4 Lotus biscoff cookies into small pieces. Add to dough.
Mix just to distribute cookies throughout dough.
Scoop dough into pan and spread or press into an even layer. Press larger biscoff cookie chunks into top of dough.
Bake for 21-24 minutes. Place on a rack to cool. After cooling a bit, drizzle with warmed cookie butter spread. Once fully cooled, slice and serve.
For best results (and neat slices), wait until the bars are completely cool before cutting into pieces. They'll have a denser, fudgier texture if allowed to cool first so the butter and cookie butter can set.
Variations
I chose to make the biscoff flavor in these speculoos blondies the main focus, so I omitted additional items like white chocolate chips. Feel free to try these variations if you want a more complex flavor!
- White chocolate - Add 120 grams (4 oz, ⅔ cup) coarsely chopped chunks of white chocolate (or white chocolate chips) to the dough. Baking time may need to be increased a few minutes due to additional volume.
- Extra spice - For an extra big punch of speculoos flavor, add 1 teaspoon cinnamon and ¼ teaspoon nutmeg (freshly grated if you have it) to the dry ingredients.
- Chocolate chips - Add 113 grams (4 oz, ⅔ cup) chopped chocolate or chocolate chips to the dough. Baking time may need to be increased by a few minutes due to additional volume.
Equipment
Square metal pan - I use this 8 x 8 metal pan to bake most of my bar cookies.
Glass and metal pans conduct heat differently. Glass bakeware takes longer to heat up than metal pans, and retains heat for longer once hot. Using a glass pan without adjusting this recipe might result in overbaked edges, as the dough will take longer to cook, and might bake too long towards the sides.
If you only have a glass pan, you may need to experiment with lowering the heat by 25 degrees Fahrenheit and baking for an additional 10 minutes. King Arthur Baking has visual examples of recipes tested using different pans here.
Parchment paper is great for lining the baking pan. The cookies won't stick at all if you use parchment paper underneath. You don't have to grease the pan and can often simply wipe it down rather than needing to wash it after baking.
Storage
Store cooled cookie butter bars in an airtight container at room temperature for up to a week. Good luck - ours always get eaten after a day or two!
Freeze blondies in an airtight container or zipper sealed bag with parchment paper between layers for 2-3 months.
Recipe tip
If you make the blondie dough quickly, the melted butter will still be warm, and the dough will have a thinner consistency. If you make the dough slowly (or barely melt the butter), the dough will begin to firm up and you'll need to press it into the pan.
Either way is OK! I baked batches with both thinner and thicker dough and the final result was the same.
Frequently asked questions
Cookie butter also goes by the name biscoff spread or speculoos spread. It is a blended paste made of speculoos cookies, oil, flour and sugar and has a similar consistency to peanut butter. It comes in both crunchy and creamy varieties.
Cookie butter was first introduced in the early part of the 2000s by several competitors on a Belgian TV show featuring inventors, De Bedenkers ("The Inventors.") Lotus Biscoff went on to purchase the recipe from the inventors and incorporate the product into their sales.
Though the terms are similar, the two cookie varieties are actually different from each other. Speculaas cookies originated in the Netherlands and are full of flavorful spices, much like gingerbread. Speculaas spice commonly includes cinnamon, nutmeg, cardamom, white pepper, cloves, ginger, allspice and cloves.
Speculoos cookies, on the other hand, are from Belgium. They use far less spice than the Dutch version as spices were much more expensive to import to Belgium. These cookies frequently contain only cinnamon, and sometimes nutmeg. The main flavor is a rich caramel taste, which comes from the unique flavor of Belgian brown sugar.
Belgian brown sugar is made from beet sugar that has been caramelized and has a rich, dark flavor profile. This contrasts to most brown sugar in the US, which is made from beet or cane sugar that has had molasses added to it.
Biscoff is the most popular brand of speculoos cookies, made by the Lotus Biscoff brand. They have been making their unique version of speculoos cookies in Lembeke, Belgium since 1932.
Love this recipe? Please leave a comment and star rating. ★★★★★ Your feedback, suggestions, and adaptations are very helpful to other bakers!
📖 Recipe
Biscoff Blondies
INGREDIENTS
Biscoff Blondies
- 113 grams (4 ounces, 8 Tablespoons) unsalted butter
- 175 grams (¾ cup + 2 Tablespoons) brown sugar
- 90 grams (6 Tablespoons) cookie butter, creamy (speculoos or biscoff)
- 2 large egg yolks
- 1 teaspoon vanilla extract
- ½ teaspoon kosher salt
- 150 grams (1¼ cups) all purpose flour
- 4 biscoff cookies , broken into blueberry sized pieces
Biscoff Blondie Topping
- 2 biscoff cookies, broken into blueberry and cherry sized pieces
- 30 grams (2 Tablespoons) cookie butter, creamy (speculoos or biscoff)
INSTRUCTIONS
- Place rack in center of oven and preheat to 350° Fahrenheit (177° Celsius, Gas mark 4).
- Line an 8 inch square (20 cm) metal baking pan with parchment paper, extending it up opposite sides as a handle to lift out the baked blondies. I use binder clips to clip the paper to the sides so that it doesn't slump into the dough.
- In a microwave safe bowl, heat butter and brown sugar in 30 second bursts until fully melted, 60-90 seconds. Whisk until the mixture looks smooth and glossy. Add cookie butter spread and whisk until fully incorporated. If the mixture starts to look curdled, don't worry! The next addition will smooth it back out again.113 grams (4 ounces, 8 Tablespoons) unsalted butter, 175 grams (¾ cup + 2 Tablespoons) brown sugar, 90 grams (6 Tablespoons) cookie butter
- Add egg yolks, vanilla and salt. Whisk thoroughly. With a spoon or spatula, mix in flour.2 large egg yolks, 1 teaspoon vanilla extract, ½ teaspoon kosher salt, 150 grams (1¼ cups) all purpose flour
- Stir in the 4 biscoff cookies that have been broken into small pieces. Mix in just until distributed throughout dough.4 biscoff cookies
- Scoop the dough into the pan and gently press it evenly into the corners. Press the larger broken pieces of remaining 2 biscoff cookies into the dough.2 biscoff cookies
- Bake for 21-23 minutes, until center is fully set, top is golden brown, and bars are pulling away from the pan at the edges.
- Once somewhat cool, gently warm the remaining 2 Tablespoons of cookie butter in 5 second bursts in the microwave (or in a double boiler over a bowl of hot water).30 grams (2 Tablespoons) cookie butter
- Using a spoon, drizzle runny cookie butter over the bars. Wait until blondies are fully cooled before cutting into pieces.
EQUIPMENT
NOTES
- If you make the blondie dough quickly, the melted butter will still be warm, and the dough will have a thinner consistency.
- If you make the dough slowly (or barely melt the butter), the dough will begin to firm up and you'll need to press it into the pan.
- Either way is OK! I baked batches with both thinner and thicker dough and the final result was the same.
- For best results (and neat slices), wait until the bars are completely cool before cutting into pieces.
- They'll have a denser, fudgier texture as the butter and cookie butter will solidify as they cool.
- Store cooled bars in an airtight container at room temperature for up to a week. Good luck - ours always get eaten after a day or two!
- Freeze in an airtight container or zipper sealed bag with parchment paper between layers for 2-3 months.
This post was originally published June 22, 2022. It has been updated to include labeled ingredient images and step-by-step photos for making the recipe.
Lisa Bourque says
Be aware that when you click on 2x or 3x the recipe, some of the ingredients do not change in the tbsp quantity, pay attention to the grams. I wish I had of noticed before I added the flour and realized it was much too thick.
Kathleen Culver says
Hi Lisa,
Thank you for your comment.
I have to manually add the additional measurements and code them to multiply accordingly - sometimes I miss one!
The recipe is now updated and will multiply accordingly.
Much appreciated,
Kathleen