These Biscoff blondies are soft and chewy cookie bars filled with both cookie butter and chopped Biscoff cookies, for plenty of warm spice flavor and sweetness. They make a great dessert for potlucks, holiday gatherings, bake sales, and more.
Preheat oven to 350F and grease a 9x13" baking pan. Set aside.
In the bowl of a stand mixer fitted with a paddle attachment (or in a large mixing bowl with an electric hand mixer), combine butter, brown sugar, and sugar. Beat on medium-high speed until light and fluffy.
Add cookie butter spread and mix to combine.
Add egg, egg yolk, and vanilla extract, mixing on medium speed to combine.
In a separate mixing bowl, whisk together flour, cinnamon, baking powder, baking soda, and salt.
With the mixer on low speed, gradually add the flour mixture to the wet ingredients, mixing only until a soft dough forms and the ingredients are incorporated.
Coarsely chop 7 of the Biscoff cookies and add the pieces to the batter. With the mixer on low speed, mix just until combined.
Press batter evenly into the prepared pan (I just use my fingers for this).
Coarsely chop the remaining 3 Biscoff cookies and sprinkle the pieces over the top of the batter, using your fingers to press them lightly into the batter.
Bake in preheated oven for about 26-32 minutes, or until center is just set.
Let cool completely in the pan, then slice and serve.
Notes
I used Biscoff cookies and Biscoff cookie butter, but any brand of speculoos cookies or cookie butter should work fine.
Leftovers can be stored in an airtight container at room temperature for up to 3-5 days.