Place the butter in a medium saucepan and melt over medium heat, stirring often, until it foams, smells nutty, and browns. This will take about 5 to 7 minutes. Scrape the browned butter into a small bowl. Place in the fridge while you prep the other ingredients, for about 10 minutes, so it can cool down a bit.

In a medium bowl, whisk together the flour, baking soda, baking powder, salt, and cinnamon.

In the bowl of a stand mixer with the beater blade, combine the brown sugar, granulated sugar, and browned butter. Mix until combined. Add the Biscoff cookie butter and mix until smooth. Scrape down the sides of the bowl with a spatula.

Add the eggs and vanilla extract and mix until combined.

Add the dry ingredients and mix on low until just combined. Don’t over mix. Stir in the chocolate chips or chocolate chunks.

Chill the dough in the refrigerator for 30 minutes. Note-you can chill the dough for up to 72 hours.

Preheat the oven to 350 degrees F. Line a large baking sheet with parchment paper or a Silpat baking mat.

Roll the cookie dough into balls, about 2 tablespoons of dough per cookie. Place the dough balls on the prepared baking sheet, about 2-inches apart.

Bake for 10 to 12 minutes or until cookies are golden brown around the edges but still a little soft in the center.

Remove from the oven and immediately sprinkle with flaky sea salt. Let the cookies cool on the baking sheet for 5 minutes. When they are set up, transfer to a cooling rack to cool completely.