Introduction

This Sour Cream Streusel Coffee Cake is a delightful treat perfect for breakfast or dessert. Its tender crumb, sweet cinnamon streusel layers, and smooth icing make it an irresistible classic. You’ll love the balance of flavors and textures in every bite.

The image shows a close-up of a two-layer crumb cake slice on a white plate with black detailing on the rim, set on a white marbled surface. The bottom layer is a light yellow dense cake with a middle layer of brown cinnamon crumble filling. The top layer is a thicker, crumbly brown topping with a rough texture, drizzled with white icing lines running vertically across it. Some crumbs are scattered around the plate, and a piece of cinnamon stick is visible at the front edge. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

3 cups all purpose flour (spooned and leveled)
1 cup brown sugar (packed)
1/2 cup granulated sugar
1 teaspoon kosher salt
2 tablespoons cinnamon
1 cup butter (2 sticks, melted)
2 1/4 cups all purpose flour
1 1/4 cups granulated sugar
1 tablespoon baking powder
3/4 teaspoon baking soda
3/4 teaspoon kosher salt
3/4 cup butter (1 1/2 sticks, softened but still cool)
1/2 cup sour cream
4 large eggs
1 cup sour cream
1 tablespoon vanilla extract
1/4 cup butter (half stick, very soft)
1 teaspoon vanilla extract
1/2 teaspoon kosher salt
1/4 cup milk (more to taste)
2 cups powdered sugar

Instructions

Step 1: Preheat your oven to 350°F. Grease a 9×13 inch cake pan with nonstick spray or butter.
Step 2: Make the streusel by whisking 3 cups flour, 1 cup brown sugar, 1/2 cup granulated sugar, 1 teaspoon salt, and 2 tablespoons cinnamon in a large bowl.
Step 3: Melt 1 cup butter in the microwave and pour it into the streusel mixture. Stir until it looks like wet sand with chunks. Do not smooth it out.
Step 4: For the cake batter, whisk 2 1/4 cups flour, 1 1/4 cups sugar, baking powder, baking soda, and 3/4 teaspoon salt in a large bowl or stand mixer.
Step 5: Chop the 3/4 cup softened butter into chunks and add it along with 1/2 cup sour cream to the dry ingredients. Beat with a paddle attachment or electric beaters until the mixture forms a ball, scraping the bowl as needed. Do not overmix.
Step 6: In a separate bowl, whisk together 4 eggs, 1 cup sour cream, and 1 tablespoon vanilla until well blended.
Step 7: Add the egg mixture to the flour mixture in three additions, beating 20 seconds after each. After the last addition, beat for 1 minute until light and fluffy.
Step 8: Spread 2 cups of batter evenly into the prepared pan. Sprinkle 1 cup of streusel over the batter, breaking up large pieces.
Step 9: Spread another 2 cups of batter over the streusel layer as evenly as possible.
Step 10: Add another 1 cup of streusel on top of the batter.
Step 11: Spread the remaining batter evenly over the streusel layer.
Step 12: Spread 2 cups of streusel evenly on top of the cake. Reserve remaining streusel on a baking sheet to dry.
Step 13: Bake the cake for 25 minutes at 350°F.
Step 14: Quickly remove the cake from the oven and sprinkle the remaining streusel evenly over the top, focusing on areas where the batter has puffed up. Return the cake to the oven promptly, keeping the door closed as much as possible.
Step 15: Bake for an additional 20-25 minutes. The total bake time will be about 45-50 minutes. Test doneness by inserting a toothpick into the center; it should come out clean with no wet batter. The cake should not wobble when the pan is shaken.
Step 16: Let the cake cool on a wire rack for 15-20 minutes before slicing.
Step 17: For the icing, beat 1/4 cup very soft butter in a medium bowl until smooth. Add 1 teaspoon vanilla, 1/2 teaspoon salt, 1/4 cup milk, and 2 cups powdered sugar. Beat until smooth.
Step 18: Drizzle the icing over the cake. You can cover the entire cake or drizzle individual servings.
Step 19: Serve the cake warm. If serving after cooling, microwave individual slices for 10-20 seconds.

Tips & Variations

Use room temperature eggs and softened butter for the best batter consistency.
For an extra twist, add chopped nuts like walnuts or pecans to the streusel.
If you prefer a tangier flavor, substitute some sour cream with Greek yogurt.
Using a glass pan may increase baking time slightly; watch the cake closely.

Storage

Keep the cake covered at room temperature for 2-3 days to maintain freshness. After that, refrigerate it, tightly wrapped or in an airtight container. Warm slices briefly in the microwave before serving to restore softness.

How to Serve

A glass baking dish filled with a dessert cut into square pieces, each piece showing a thick crumbly layer on top with a golden brown color and some darker baked spots; the crumb layer looks crunchy and uneven with small clumps scattered across the surface; thin white icing is drizzled in diagonal lines evenly across the entire top, adding contrast; the dish is placed on a white marbled textured surface. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this cake gluten-free?

Yes, you can substitute the all-purpose flour with a gluten-free baking blend, but make sure it includes xanthan gum for structure. Baking times may vary slightly.

Can I prepare the streusel ahead of time?

Absolutely. The streusel can be made a day in advance and stored in an airtight container at room temperature. This helps the flavors meld and saves time on baking day.