Moist Crumb Cake
This classic crumb cake is topped with big, fat crumbs and has a sweet stripe of cinnamon and sugar down the middle. Sour cream makes it nice and moist!
This is the perfect brunch cake, but it’s also wonderful for snacking on at any time of the day. I can’t help but pick crumbs off the top whenever I walk by.
The ingredient that makes this cake itself stand out is the sour cream. I use full-fat sour cream and highly recommend you do the same. The cake won’t taste exactly the same if you make a substitution, but you can use yogurt or Greek yogurt if that’s what you have on hand.
Rolled oats, not steel-cut oats, are essential for the amazing crumb topping.
The rest of the recipe’s ingredients are pantry staples – sugar, brown sugar, cinnamon, butter, eggs, flour, and the like.
How It’s Made
Start by mixing cinnamon and sugar in a bowl and putting that aside. You’ll use it in a bit.
Next, cream butter and sugars in a mixing bowl until the mixture is light and fluffy. Beat in eggs, one at a time, then add the sour cream and vanilla.
In a separate bowl, whisk together dry ingredients – flour, baking powder, and salt. Add the dry ingredients a little bit at a time to the wet mixture until everything is just combined.
Now comes one of my favorite parts of this cake – the cinnamon sugar layer. It’s really easy to add; spread half of the batter in the pan, and then top with cinnamon and sugar.
Cover that layer with the second half of the batter.
Crumb cake would just be cake without the topping. People make crumb topping in many different ways, but my favorite topping is a mixture of melted butter, brown sugar, flour, and rolled oats. Spread the crumbs over the top of the cake before baking.
Once the cake is out of the oven, let it cool to room temperature and dust with cinnamon and powered sugar.
Expert Tips and FAQs
I’ve done extensive testing and I’ve found that you can replace the sour cream with yogurt or Greek yogurt and not notice any difference in texture. Use whatever you have on hand.
I dust the cake with cinnamon and powdered sugar when I’m done because I love the taste and look. Although the cake is quite sweet and doesn’t really need it, it also looks nice with a simple glaze made of milk and powdered sugar.
This cake lasts about three days in an airtight container. But, you can also freeze it for months or freeze individual slices and bring to room temperature before enjoying.
Cinnamon Sugar Ingredients
- 1/2 cup granulated sugar
- 1 tablespoon cinnamon
- 1 cup unsalted butter room temperature
- 3/4 cup light brown sugar
- 1/2 cup granulated sugar
- 2 large eggs
- 1 cup full-fat sour cream
- 1/2 teaspoon vanilla extract
- 2 cups all-purpose flour
- 1 teaspoon baking powder
- 1/8 teaspoon salt
- 1/2 cup unsalted butter melted
- 1 1/4 cups all-purpose flour
- 6 tablespoons light brown sugar same as 1/4 cup + 2 tablespoons
- 6 tablespoons rolled oats same as 1/4 cup + 2 tablespoons
Cinnamon Sugar Instructions
- Mix ingredients in a small bowl and set aside.
- Preheat oven to 350 F.
- Beat butter, brown sugar, and white sugar in a medium-sized mixing bowl until light and fluffy.
- Beat in eggs one at a time.
- Beat in sour cream and vanilla.
- In a separate medium-sized mixing bowl, whisk together flour, baking powder, and salt.
- Add flour mixture to wet ingredients a little bit at a time until just combined.
- Spread half of the batter into a greased 8" square cake pan.
- Spread cinnamon sugar mixture evenly over the poured batter.
- Top with the remaining batter.
Crumb and Baking Instructions
- Mix all ingredients in a small bowl until large crumbs form.
- Top the batter with the crumbs.
- Bake for 75 minutes or until a toothpick inserted into the center of the cake comes out clean.
- Optionally, sprinkle with a little more cinnamon and dust with powdered sugar.
Join my mailing list - and receive a free eBook!