• Preheat an oven to 180c (350f) and prep a donut pan on the side.
• Into a big mixing bowl, add the flour, baking powder, baking soda, kosher salt, sugar, and cinnamon, and mix with a whisk until combined.
• Then add the buttermilk, eggs, oil, and the melted biscoff spread. Fold lightly with a spatula until the mixture is just combined and you cant see big lumps of flour.
• Transfer the batter into a piping bag and cut a small hole in the tip of the bag. Butter the donut pan with room temperature butter and pipe the batter into the donut pan ¾ way full.
• Bake in a 180c (350f) preheated oven for 9-11 minutes or until a toothpick inserted into the donuts comes out clean.
• Remove the baking pan from the oven and let it cool for 5 minutes. Then remove it from the pan and let it cool on a cooling rack to cool completely.

Make The Biscoff Glaze:

• Into a medium-sized mixing bowl, add the powder sugar, milk, vanilla extract, and biscoff spread. Mix with a spoon until smooth and silky.
• Feel free to adjust the consistency by increasing and decreasing the milk to your liking.

Assembly:

• Dip the donuts in the glaze and let them drip on a cooling rack. Top the donuts with biscoff cookie crumbs.