Sour Cream Coffee Cake

INGREDIENTS

For the Cinnamon Filling

• ⅔ cup packed light brown sugar (147g)
• ¼ cup all-purpose flour (30g)
• 2 teaspoons ground cinnamon

For the Streusel Topping

• ¾ cup all-purpose flour (90g)
• ½ cup packed light brown sugar (110g)
• 2 teaspoons ground cinnamon
• ¼ teaspoon salt
• 6 tablespoons cold unsalted butter diced (85g)

For the Cake

• 1¾ cups all-purpose flour (210g)
• 2 teaspoons baking powder
• ¾ teaspoon salt
• 10 tablespoons unsalted butter softened (142g)
• ¾ cup granulated sugar (150g)
• ¼ cup packed light brown sugar (55g)
• 2 large eggs room temperature
• ⅔ cup sour cream room temperature (160g)
• 2 teaspoons vanilla extract

For the Vanilla Glaze (optional)

• 1 cup powdered sugar (120g)
• 2 tablespoons whole milk
• ½ teaspoon vanilla extract

DIRECTIONS

For the Cinnamon Filling

1. In a small bowl whisk together the brown sugar, flour, and cinnamon. Set aside.

For the Streusel Topping

1. In a medium bowl, whisk together the flour, brown sugar, cinnamon, and salt. Add the diced butter. Use your clean fingers or the tines of a fork to press and crumble the butter into the dry mixture until the mixture is cumbly 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

1. Preheat the oven to 350°F. Lightly grease 8×8-inch square baking pan and line with parchment paper.
2. In a medium bowl, whisk together the flour, baking powder, and salt.
3. 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 the bowl down then add the sour cream and vanilla and mix on low speed until combined. Scrape down the bowl.
4. Add the dry mixture to the wet mixture and beat on low speed until just until combined, then use a spatula to scrape the bowl down and mix any stray bits in.
5. Spread half the of cake batter into the prepared pan and smooth out. Sprinkle the Cinnamon Filling on top. Dollop the remaining batter over the cinnamon filling, then spread it out into an evenly 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 helps keep make sure there’s enough topping on the edges to keep the cake from rising unevenly.
6. 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.

For the Glaze

1. If making the glaze, whisk together the powdered sugar, milk, and vanilla in a small bowl until smooth. Drizzle over the coffee cake before or after slicing.

NOTES

• Ingredient temperature matters for the best coffee cake! For the streusel topping, you need cold butter so you can form crumbles. For the cake batter, you need room temperature butter to whip up nice and fluffy, and room temp eggs and sour cream so they incorporate better into the butter.
• Be aware of the consistency of the cake batter. The batter may look thicker than you expect, and that’s normal! A thin batter will cause the cinnamon-sugar filling and streusel topping to sink into the batter and likely end up on the bottom of the pan.
• Line the baking dish with parchment paper. This makes removing the cake from the pan a breeze!
• Use my trick to spread the remaining batter over the cinnamon filling: This can be a little tricky. Spreading the batter from the center towards the edges and then making sure the batter touches the parchment paper is the easiest way. Try to avoid back-and-forth motions, as it can cause the batter to peel up and the cinnamon-sugar filling to get mixed into the batter. The cake will still bake up just fine if that happens; it will just have a less defined center stripe of filling.
• To help the cake rise more evenly: Because the streusel topping weighs the batter down a bit on top, it can rise unevenly or be enveloped by the rising batter if it isn’t sprinkled evenly. This tends to happen more on the edges since the batter rises there first during baking. I recommend starting along the edges when sprinkling on the topping to ensure there is enough crumb topping to cover them.