Crumb Topping 2 1/2 cups unbleached all-purpose flour (10 1/2 ounces) 1 cup granulated sugar 1/4 cup brown sugar 1/2 teaspoon salt 1 1/2 teaspoons ground cinnamon 1 cup unsalted butter, melted and cooled slightly 1 teaspoon vanilla extract 3/4 teaspoon almond extract Cake 1/2 cup unsalted butter, softened 1 cup sugar 2 large eggs 1 teaspoon vanilla extract 1 cup sour cream 2 cups unbleached all-purpose flour (8 1/2 ounces) 1/2 teaspoon baking soda 1/2 teaspoon salt 1 teaspoon baking powder
Adjust oven rack to center position and preheat oven to 350 degrees F. Grease a 9-by-13-inch pan and set aside.
Make the Crumb Topping: In a medium-sized mixing bowl, wisk together the flour, sugar, salt and cinnamon. Make a well in the center of the mixture and set aside. Melt the butter in the microwave on 50% power until just melted. Stir in the vanilla and almond extracts. Pour the melted butter mixture into the well in the center of the flour mixture. With a fork, gradually pull the flour mixture in to the butter. Continue to toss/combine until all the butter is absorbed and you have a uniformly moistened crumb mixture. If texture of crumb is too small, gently squeeze small clumps together to make large crumbs ranging in size from that of a pea to that of a grape, about 1/4 to 1/2 inch in size. If the crumb mixture forms a solid dough, simply use your fingers tor a fork to break-up the solid crumb mixture into big crumbs, about 1/4 to 1/2 inch in size. Crumbs don't have to be uniform, just try to get most about this size. Set aside while you make the cake batter.
Make the Batter: In a medium-sized bowl, whisk together the flour, baking soda, salt and baking powder. Set aside. In a large bowl, cream the butter and sugar together with an electric mixer on high speed until light and fluffy. Add the eggs, one at a time, beating after each addition. Beat in the vanilla and sour cream, scraping down the sides of the bowl with a spatula as needed. Add flour mixture to the sour cream mixture and beat on low until just combined, do not over mix. Pour the batter into the prepared pan and spread evenly. Sprinkle the crumb mixture over the batter with your fingers, covering the batter evenly and completely. Bake or 30-35 minutes. Cake is done when a wooden pick or cake tester inserted near the center comes out clean, and the sides of the cake are light golden brown and slightly pulling away from the edge of the pan. Remove from the oven and let the cake cool in its pan set on a wire rack. Dust with confectioners' sugar, if desired.