Place stick of butter in the freezer for about 20 minutes
Combine the dry scone ingredients: flour, baking powder, baking soda, cinnamon, salt and mix in a large bowl.
Remove butter from freezer, and using a coarse grater grate half the stick of butter into the flour mixture. Using a fork, mix and fluff butter into flour. Grate the rest of the stick of butter into the flour and repeat fluffing/mixing.
Create a well in the center of flour mixture and pour your beaten egg and heavy cream into it.
Using a fork, push sections of flour into the liquids, creating a very rough mixture.
When the liquids are mostly incorporated but before dough has come together, add cookie butter into dough in spoonfuls around the bowl.
Begin to bring the dough together more, distributing the cookie butter while you do. Cookie butter will not be evenly distributed but sort of marbled throughout the dough.
Empty bowl onto counter and bring the dough together, folding it over on itself 2-3 times, then shaping it into a circle or square that is about 1½" tall.
Using a bench scraper or knife, cut the dough into 8 equal wedges. When cutting do not use a sawing motion but rather cut down from the top all the way through in one motion.
Place scones on parchment lined baking sheet and place in the freezer.
Preheat oven to 425°F
In a small/medium bowl mix together your crushed biscoff cookies, flour, brown sugar and pinch of salt.
Melt your 3 tbsp of butter and pour over the streusel dry ingredients.
Use a fork to mix the mixture together until no dry pieces remain.
Remove scones from freezer, and place a spoonful of streusel on top of each. I found it easier to use my fingers than a spoon.
Place scones back in the freezer for another 10-15 minutes.
Put scones in oven on middle rack, and immediately reduce oven temperature to 375°F.
Bake scones for about 25 minutes. When scones are ready, remove from oven and place on a wire rack to cool.
