Ingredients
⅓cupgranulated sugar
⅓cupbrown sugar
¾tspcinnamon
⅛tspsalt
½cupbutter,melted
1¾cupcake flour
1¼cupcake flour
½cupgranulated sugar
¼tspbaking soda
¼tspsalt
6tbspbutter,cut into pieces, softened but cool
1egg
1egg yolk
1tspvanilla
⅓cupbuttermilk
powdered sugar,for dusting
Preparation
Preheat oven to 325 degrees F and adjust an oven rack to the upper middle position. Line a 8×8-inch square pan with parchment paper, with enough paper to fold over the sides. Set aside.
Whisk together the granulated sugar, brown sugar, cinnamon, salt and flour. Pour melted butter over the mixture and use a rubber spatula or wooden spoon to mix thoroughly. Mixture will be thick and doughy. Set aside.
With a hand or stand mixer, combine the flour, sugar, baking soda and salt and mix to combine. With mixer on low, begin adding the pieces of butter one at a time. Continue mixing until mixture resembles moist crumbs with no visible butter chunks remaining.
Add egg, yolk, vanilla and buttermilk. Beat at medium for 1 to 2 minutes until the batter becomes light and fluffy, scraping down the sides of the bowl if necessary.
Spread the batter evenly into the prepared pan. Top the batter with the crumble topping, breaking apart any big chunks into smaller pea-sized pieces. Start at the edges and work toward the center.
Bake the cake for 35 to 40 minutes or until golden brown and toothpick inserted comes out clean and crumb-free. After baking, cool cake for at least 30 minutes.
Remove cake from pan by lifting out of the pan by the edges of the parchment paper. Dust with powdered sugar.
