Apple Coffee Cake with Sourdough Starter

There’s nothing like a big square of coffee cake with the perfect crumbly topping. And underneath, you’ll find everything good about fall: fresh sweet apples and plenty of warm spices.  You won’t taste the sourdough starter, but you will notice a slight tanginess in the cake.

This is the perfect way to start those first chilly fall mornings or to serve as an after-dinner dessert. The crumbly topping is so yummy. I often make a double batch because everyone (including me) wants seconds.

Ingredients and Tools You’ll Need

Don’t skip the boiled cider. If you can get your hands on some, boiled cider adds so much flavor to the cake. Any type of apple will do here. Use cold butter for the topping to get those crumbly pieces. If your butter is too soft, the topping might melt into the cake instead of staying crunchy. If you don’t have a starter on hand, you can make your own, but it takes a few days, so plan ahead.

This makes 9 servings and freezes well. If you’d like to double or triple this recipe, you can make adjustments in the recipe card at the bottom of this post.

Equipment

• 9×9 or 8×8 baking pan
• Large mixing bowl
• Pastry blender (for blending butter and flour)

Ingredients

For the Cake

• ½ cup butter (softened)
• 1 cup granulated sugar
• 2 eggs
• 1 teaspoon vanilla extract
• 2 cups all-purpose flour
• 1 teaspoon baking powder
• ½ teaspoon baking soda
• ½ teaspoon salt
• 1 teaspoon ground cinnamon
• ½ teaspoon ground nutmeg
• ¼ teaspoon ground allspice
• ¼ teaspoon ground cloves
• ½ cup sourdough starter
• ½ cup sour cream or Greek yogurt
• 1 large apple (peeled, cored, and diced, about 1 ½ cups)
• 3 tablespoons of boiled cider (optional, but adds great flavor)

For the Topping

• ½ cup cold salted butter diced
• ½ cup all-purpose flour
• 1 cup brown sugar
• 1 tablespoon ground cinnamon
• ¼ teaspoon ground nutmeg

How to Make Sourdough Apple Coffee Cake

Step One: Make the Batter

Turn your oven to 350°F and spray a 9×9 pan (8×8 works too, but it’ll be a bit thicker).

Cream your butter and sugar until it’s fluffy – this takes a few minutes, so don’t rush it. Beat in your eggs and vanilla.

In another bowl, whisk together all your dry stuff: flour, baking powder, baking soda, salt, and all those spices.

Now here’s where it gets a little tricky – you’re going to add the dry ingredients to your butter mixture, but alternate with the sourdough starter and sour cream. Start with some flour mixture, then some starter, then more flour, then sour cream, and finish with flour. The batter’s going to be THICK. Like, really thick. That’s normal.

Fold in your diced apples. I peel mine because I don’t love apple skin in cake, but you leave them in if you want.

Step Two: Make the Topping

Cut the cold butter into the flour until it looks like peas. Stir in the brown sugar, cinnamon, and nutmeg. This is going to be chunky and perfect.

Step Three: Assemble and Bake

Spread that thick batter in your pan – you might need to really work at it since it’s so dense. Then sprinkle all that topping over it.

Bake for 40-45 minutes. Stick a toothpick in the center – if it comes out clean, you’re done. Let it cool for at least 15 minutes or you’ll burn your tongue.

Cut it right in the pan and serve. No need to get fancy with it.

Storage Instructions

Place any leftovers in an airtight container on the counter for 3 days, or you can store it in the fridge for a week. Make sure it’s well-covered to prevent it from drying out.

You can also freeze this. Wrap individual pieces tightly in plastic wrap, then place them in a freezer-safe bag or container. You can freeze the cake for up to three months. When you’re ready to enjoy it, let it thaw at room temperature or warm it gently in the oven.

More Cake Recipes For Your Starter

• This sourdough apple cake is similar to this cake but it has a cream cheese frosting.
• Triple berry coffee cake tastes like dessert but it’s got fruit so you can serve it for breakfast.
• This classic sourdough banana bread is one of my most popular recipes (online AND in real life).
• Another delicious cake for fall is sourdough pumpkin cake – a perfect way to kick of pumpkin spice season.

Printable Recipe