Prepare the streusel filling: In a medium sized bowl combine the flour, brown sugar, cinnamon and salt together. Then work in the butter until small clumps form. (I just use my fingers to work it together). Refrigerate.

1/2 cup all purpose flour,1/3 cup brown sugar, packed,2 tsp. cinnamon,pinch salt,5 Tbsp. softened butter, unsalted

Preheat the oven to 400°F. Line two baking sheets with parchment paper or silicone baking mats. Set aside

Combine the dry ingredients in a large bowl: all purpose flour, cake flour, corn starch, cinnamon, baking soda, baking powder and salt. Set aside.

1 1/4 cup all purpose flour,3/4 cup cake flour,1 tsp. cornstarch,1 tsp. cinnamon,1/2 tsp. baking soda,1/2 tsp. baking powder,1/2 tsp. salt

Place the cubed butter and sugars into the bowl of a stand mixer and secure the paddle attachment. Turn the mixer on and cream until smooth, about 1-2 minutes.

8 Tbsp. cold butter, unsalted, cut into cubes,1/2 cup brown sugar, packed,1/4 cup sugar

Add in the egg, egg yolk and vanilla extract and blend until mixed. Use a rubber spatula to knock off mixture if any is sticking to the sides of the bowl and mix again.

1 tsp. vanilla extract,1 large egg,1 large egg yolk

Gradually add in the dry ingredients, about 1/4 cup at a time. Mix until incorporated.

Scoop and roll cookie dough into ~8 large balls, or smaller if preferred. Place on prepared baking sheets.

Make an indent in each cookie, using your thumb or the end of a spoon/spatula or something similar. (I used the end of a wooden juicer).

Spoon ~1 Tbsp. of the streusel filling in each cookie and bake for ~9-11 minutes, or until edges appear set and are slightly golden. (They will continue to bake a bit more on the pan after you pull them out so pull them out just before you think they're done so they don't over-bake/become dry.)

*Optional step to get cookies perfectly circular: Immediatley after the cookies come out of the oven, place a circular cookie cutter or a circular drinking glass around one of the cookies (it should be larger than the cookie so you don’t cut off any edges) and give the cookies a spin. Swirling the cookie should help to smooth out any uneven edges.

Let cookies rest on cookie sheet for ~5 minutes then transfer to a cooling rack.

Whisk together the ingredients for the icing and once the cookies are cooled, drizzle icing over the tops and enjoy!

2 Tbsp. unsalted butter, melted,3 Tbsp. heavy cream,1 cup powdered sugar, sifted,1 tsp. vanilla,pinch salt