Optional step: Freeze small ¼ teaspoon sized scoops of cookie butter spread on a lined baking sheet about 30- 60 minutes before baking the cookies. Pull out the eggs and butter to come to room temperature.
Preheat the oven to 350 F (177 C). Line two large aluminum baking sheets with parchment paper. Set aside.
In a small mixing bowl whisk the flour, baking powder and salt together.
In a large mixing bowl beat together room temperature butter and Biscoff cookie butter spread until smooth.
On medium-high beat in the light brown sugar and granulated sugar until light in color. This takes about 2-3 minutes.
On low, beat in the eggs, egg yolk and vanilla extract until smooth and well combined.
Stir in the dry ingredients until just combined.
Fold in the chocolate chips and frozen cookie butter pieces (if using). Tip: Reserve ½ cup of chcolate chips for topping the cookies before baking.
Using a medium cookie scoop, drop 2 tablespoon (30 ml) sized balls of cookie dough onto the prepared baking sheets about 3 inches apart. Cover the remaining cookie dough with plastic wrap and store in the fridge until ready to bake.
Bake at 350 F (177 C) for 12 - 16 minutes. The edges should be lightly golden and set with barely set centers.
Cool the Biscoff cookies on the hot baking pan for 3 - 4 minutes before transferring them to a cooling rack. During this time, you can also add a few more dollops of cookie butter on top of the hot cookies.