Preheat the oven to 350F degrees.

Lightly spray a 9x13 inch pan non-stick cooking spray and then with parchment paper, leaving an overhang around the edges.

In a large bowl, using a mixer, beat together the butter, Biscoff spread, brown sugar and white sugar until no lumps remain.

Then mix in the eggs and vanilla extract.

Add and mix in the flour, baking powder and salt until just combined.

Stir in the chocolate.

Spoon the batter into the prepared pan and smooth the top.

Place in the preheated oven in the middle rack and bake for 30 minutes, or until an inserted toothpick comes out clean or with a few crumbs. It may take anywhere between 25-35 minutes, depending on your oven.

Remove from the oven and place the pan on a wire rack to cool, keeping the bars in the pan. Add more chocolate to the tops if desired.

Cool bars for at least 45 minutes, or until room temperature, for nice bar cutting.

To slice the bars, lift them out of the pan using the parchment paper overhang. Place on a cutting board and slice.