Cinnamon Streusel Coffee Cake That Stays Moist for Days

This cinnamon streusel coffee cake is supremely moist from buttermilk and sour cream, with a thick ribbon of cinnamon sugar running through the middle and a crackly brown sugar crumb on top.

It’s the kind of cake that actually tastes better on day two, making it perfect for a lazy weekend breakfast or a make-ahead brunch.

Why This Coffee Cake Stays in the Rotation

I’ve made a lot of coffee cakes over the years, but this is the one that earns its spot in the rotation.

The double layer of cinnamon streusel, a thick seam of sugar in the middle and a crackly crumb on top, means every bite has a buttery crunch.

And thanks to buttermilk and sour cream, the crumb stays tender for days. It’s the cake I bake on Friday and slice all weekend.

Ingredients

• 2 cups all-purpose flour: spooned and leveled, not scooped
• 1 tsp baking powder
• 1/2 tsp baking soda
• 1/2 tsp fine sea salt
• 1/2 cup unsalted butter, softened: for the cake
• 1 cup granulated sugar
• 2 large eggs: room temperature works best
• 1 cup buttermilk: room temperature
• 1/4 cup sour cream: full-fat gives the richest crumb
• 2 tsp vanilla extract
• 1/4 cup granulated sugar: for the cinnamon-sugar ribbon
• 1 tsp ground cinnamon: for the ribbon
• 1 cup all-purpose flour: for the streusel
• 1/2 cup packed brown sugar: light or dark, both work
• 1/4 cup granulated sugar: for the streusel
• 1 tbsp ground cinnamon: for the streusel
• 1/2 cup cold unsalted butter: cut into small pieces for the streusel

Variations / Substitutions

• No buttermilk: stir 1 tablespoon lemon juice or white vinegar into 1 cup milk and let it sit 5 minutes.
• No sour cream: plain Greek yogurt works just as well.
• Add nuts: fold 1/2 cup chopped pecans or walnuts into the streusel for extra crunch.

Overnight Cinnamon Roll Breakfast Casserole makes a great breakfast to go with this coffee cake.

How To Make Cinnamon Streusel Coffee Cake

Step 1: Make the Cinnamon Streusel

Preheat your oven to 350°F (175°C) and make the streusel. In a medium bowl, whisk 1 cup flour, 1/2 cup packed brown sugar, 1/4 cup granulated sugar, and 1 tablespoon cinnamon. Pinch the 1/2 cup cold butter pieces into the dry ingredients until the mixture looks like damp sand with some pea-sized clumps. Set it aside.

You want a mix of fine crumbs and larger nuggets for texture. If everything gets too fine, it’ll melt into the cake instead of staying crunchy.

Step 2: Mix the Cinnamon Sugar Filling

In a small bowl, stir together 1/4 cup granulated sugar and 1 teaspoon cinnamon. This is the ribbon that runs through the middle of the cake, giving you those sweet, dark swirls.

Resist the urge to add more. The sugar layer will melt and create a moist seam while the cinnamon concentrates its warmth.

Step 3: Cream the Butter and Sugar

In a large bowl, beat 1/2 cup softened butter and 1 cup granulated sugar with an electric mixer on medium speed until light and fluffy, about 3 minutes. Beat in 2 large eggs one at a time, then 2 teaspoons vanilla, 1/4 cup sour cream, and a pinch of the 1/2 teaspoon salt.

The mixture will look curdled after adding the sour cream. That is fine. With the mixer on low, add 1 cup buttermilk and the remaining salt, then gradually mix in 2 cups flour, 1 teaspoon baking powder, and 1/2 teaspoon baking soda just until no dry streaks remain. Overmixing makes the cake tough, so stop as soon as the flour disappears.

Step 4: Layer the Batter and Streusel

Spread half the batter into a greased 9×13-inch baking dish. Sprinkle the cinnamon sugar mixture evenly over the batter, then dollop the remaining batter on top and gently spread it to the corners. Scatter the streusel over the top, breaking up any large clumps with your fingers.

Don’t press the streusel in. Let it sit on top so it bakes into craggy, golden peaks. Bake until a toothpick inserted in the center comes out with a few moist crumbs, 45 to 55 minutes. The top will be deeply golden and the kitchen will smell like warm spice.

Step 5: Cool and Slice the Coffee Cake

Let the cake cool in the pan on a wire rack for 20 minutes, then slice and serve warm. The crumb will be tender and the streusel will have set into a crackly top.

This cake slices cleanly when warm but holds together best after fully cooling. Either way, a cup of coffee next to it is mandatory.

A Few Notes Before You Start

• Make sure your buttermilk, eggs, and sour cream are at room temperature before you begin. Cold ingredients can cause the batter to seize.
• If the top is browning too fast, tent the cake loosely with foil during the last 10 minutes of baking.
• For the tallest slices, bake in a 9-inch square pan and add 5 to 10 minutes to the bake time.
• This cake freezes beautifully whole or in slices for up to 3 months.

Bake times by pan:

Keeping the Cake Moist and Fresh

• Refrigerate: store tightly covered at room temperature for up to 3 days, or refrigerate for up to a week.
• Reheating: warm individual slices in the microwave for 15 to 20 seconds, or place the whole cake in a 300°F oven for 10 minutes.
• Serve cold: the cake tastes great straight from the fridge, with the streusel still crisp.

What to Serve with Coffee Cake

A bowl of fresh fruit, like berries or citrus segments, balances the buttery richness with bright acidity. Scrambled eggs or a simple frittata on the side makes it feel like a full brunch, and a steaming mug of strong coffee or black tea is never a bad idea.

Frequently Asked Questions

Can I make this coffee cake in a bundt pan?

Yes, but you need to adjust the layering. Pour half the batter into the prepared pan, sprinkle the cinnamon sugar, then add the rest of the batter. Top with half the streusel before baking, and sprinkle the remaining streusel on after the cake has cooled slightly so it sticks.

Why did my cake turn out dry?

Most likely overbaking or packing the flour. Use a kitchen scale if you have one, or spoon the flour into the measuring cup and level it off with a knife. Check the cake a few minutes before the earliest bake time.

Can I use whole wheat flour?

You can swap up to half of the all-purpose flour with whole wheat flour, but the cake will be denser and less tender.

Why did my streusel melt flat instead of staying crumbly?

The butter may have been too warm or the streusel was mixed too finely. Keep the butter cold and stop when you have pea-sized clumps.

Cinnamon Streusel Coffee Cake Recipe

Print Recipe Pin Recipe

Prep Time 20 minutes mins

Cook Time 50 minutes mins

Total Time 1 hour hr 10 minutes mins

Servings: 12 servings

Calories: 320

Ingredients Method Notes

Ingredients

  

• 2 cups all-purpose flour
• 1 tsp baking powder
• 1/2 tsp baking soda
• 1/2 tsp fine sea salt
• 1/2 cup unsalted butter, softened
• 1 cup granulated sugar
• 2 large eggs
• 1 cup buttermilk
• 1/4 cup sour cream
• 2 tsp vanilla extract
• 1/4 cup granulated sugar (for ribbon)
• 1 tsp ground cinnamon (for ribbon)
• 1 cup all-purpose flour (for streusel)
• 1/2 cup packed brown sugar
• 1/4 cup granulated sugar (for streusel)
• 1 tbsp ground cinnamon (for streusel)
• 1/2 cup cold unsalted butter, cut into small pieces

Method

 

1. Preheat oven to 350°F (175°C). In a medium bowl, whisk the streusel flour, brown sugar, 1/4 cup granulated sugar, and 1 tbsp cinnamon. Pinch in the cold butter until crumbly.
2. In a small bowl, stir together 1/4 cup granulated sugar and 1 tsp cinnamon for the filling.
3. In a large bowl, beat the softened butter and 1 cup granulated sugar until fluffy. Beat in eggs, vanilla, sour cream, and salt, then alternately mix in buttermilk and the remaining 2 cups flour, baking powder, and baking soda until just combined.
4. Spread half the batter into a greased 9×13‑inch pan. Sprinkle the cinnamon sugar over it, dollop the remaining batter on top, and spread gently. Scatter the streusel on top. Bake 45 to 55 minutes.
5. Cool the cake in the pan on a wire rack for 20 minutes, then slice and serve warm.

Notes

The cake tastes even better the next day. Store it tightly covered. For a thicker cake, use a 9×9‑inch pan and bake 50 to 60 minutes.