• ¾ cup (94 grams) all-purpose flour
• ½ cup (110 grams) light brown sugar, packed
• 2 teaspoons ground cinnamon
• ¼ teaspoon salt
• 6 tablespoons (85 grams) unsalted butter, diced

Ingredients for Cake:

• 1¾ cups (220 grams) all-purpose flour
• 2 teaspoons baking powder
• ¾ teaspoon salt
• 10 tablespoons (140 grams) unsalted butter, softened 
• ¾ cup (150 grams) granulated sugar
• ¼ cup (57 grams) packed light brown sugar
• ¾ cup (160 grams) sour cream, room temperature
• 2 large eggs, room temperature
• 2 teaspoons pure vanilla extract

For the Streusel Topping:

In a medium bowl, whisk together the flour, brown sugar, cinnamon, and salt. Add the diced butter. Use your clean fingers to press and crumble the butter into the dry mixture until the mixture is crumbly and resembles wet sand. For larger crumbles, squeeze a handful of the mixture together and break apart into large pieces. Set aside.

For the Cake:

Preheat the oven to 350°F. Lightly grease 8″×8″ square baking pan and line with parchment paper.

In a medium bowl, whisk together the flour, baking powder, and salt.

In a large mixing bowl or the bowl of a stand mixer fitted with the paddle attachment, beat the butter and both sugars on medium speed until light and fluffy, about 3 minutes.

Add the eggs one at a time, beating well between each addition. Scrape down the bowl and beaters.

Add the sour cream and vanilla and mix on low speed until combined.

Add the dry mixture to the wet mixture and beat on low speed just until combined, then use a spatula to scrape the bowl down and mix any flour from the bottom of the bowl.

Spread half of the cake batter into the prepared pan and smooth to the sides of the pan.  The batter will be very thick.

Sprinkle the Cinnamon Filling on top of the batter.

Dollop the remaining batter over the cinnamon filling, then spread it out into an even layer by moving from the center to the edges.

Sprinkle the struesel over the top, starting at the edges, and working in towards the center.  This will make sure there’s enough topping on the edges to keep the cake from rising uneven.

Bake for 55 minutes or until a toothpick inserted in the center comes out clean.

Allow the cake to cool in the pan for 30 minutes before serving.

I hope you make this delicious treat, and if you do, please tag me on Instagram @goodeatsbymimi.  I would love to hear from you and see your beautiful photos!