0.5cupunsalted butter, softened to room temperature
1cupsour cream
2largeeggs, at room temperature
1teaspoonvanilla extract
2teaspoonsbaking powder
1teaspoonbaking soda
0.5teaspoonsalt
1tablespoonground cinnamon
0.25cuppacked brown sugar
0.5cupchopped nuts (e.g., walnuts or pecans, optional)
Instructions
Begin by preheating your oven to 350°F (175°C). Prepare a 9x13-inch baking pan by greasing it lightly with butter or oil, then dusting it with flour to prevent sticking.
In a large mixing bowl, use a hand mixer or stand mixer to cream the softened butter and granulated sugar together until the mixture is light and fluffy, about 3-4 minutes.
Incorporate the eggs into the creamed mixture one at a time, ensuring to beat well after each addition. Then, stir in the vanilla extract and sour cream until fully combined.
In a separate medium bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt to ensure even distribution of the leavening agents.
Gradually add the dry ingredients to the wet mixture, stirring gently with a spatula or wooden spoon just until combined. It’s important not to overmix; a few lumps are perfectly fine.
Prepare the streusel topping by combining the ground cinnamon, packed brown sugar, and chopped nuts (if using) in a small bowl. Mix well to combine.
Pour half of the batter into the prepared baking pan, using a spatula to spread it evenly across the bottom. Sprinkle half of the streusel mixture on top of the batter.
Carefully pour the remaining batter over the streusel layer, using the spatula to spread it gently without disturbing the first layer. Finally, sprinkle the rest of the streusel mixture evenly over the top.
Bake in the preheated oven for 30-35 minutes, or until a toothpick or cake tester inserted into the center comes out clean or with just a few crumbs attached.
Once baked, allow the cake to cool in the pan for about 10 minutes. Then, transfer it to a wire rack to cool completely.
Notes
For an elegant finishing touch, serve the cake warm or at room temperature dusted lightly with powdered sugar.