Moist Banana Coffee Cake with Sour Cream Glaze

This banana coffee cake features a cinnamon swirl through the center and a buttery cinnamon streusel on top. Made with sour cream for extra moisture and a tender crumb, this easy coffee cake requires no mixer—just a few bowls and a whisk. It’s a perfect companion to a morning or afternoon cup of coffee, and it’s a great way to use up ripe bananas.

Square slices of banana coffee cake, some slices are drizzled with a white glaze.

Fun fact: coffee cake traditionally doesn’t contain coffee. It was created to be served alongside coffee, not baked with it. This banana coffee cake is adapted from a favorite banana bundt cake and after extensive testing the cinnamon filling and streusel were perfected. A small amount of cocoa powder darkens the filling so the swirl is visible when you slice the cake, which is part of the delight.

The streusel was adjusted to be slightly crunchy without falling apart when sliced—adding a touch more melted butter keeps the topping tender yet intact.

If you have more ripe bananas to use up, other tried-and-true options include banana cake with chocolate frosting, banana cake with peanut butter frosting, or super moist chocolate chunk banana bread.

Testing and Re-testing This Cake

This banana coffee cake underwent many rounds of testing to balance banana flavor with a classic coffee cake texture. Two elements received the most attention:

  • Filling: Early versions blended into the cake because the banana and spices darkened the batter. A small dash of cocoa powder gives the filling contrast without adding chocolate flavor. One teaspoon proved to be the ideal amount.
  • Streusel Topping: The goal was a topping that provided some crunch but didn’t collapse when the cake was sliced. Increasing the melted butter and sugar while keeping the flour the same produced a slightly crunchy, cohesive streusel.

Grab Your Ingredients

All the ingredients needed to make banana coffee cake, weighed out into small bowls.
  • Bananas: Use very ripe bananas with lots of brown spots—easier to mash and sweeter in flavor.
  • Sour Cream: Adds tang and keeps the cake moist and tender; full-fat works best.
  • Cocoa Powder: A small amount in the filling deepens the color so the cinnamon swirl is visible without lending a chocolate taste.

Let’s Make This Recipe

A large white bowl with cinnamon and brown sugar in it.
  1. Step 1: Whisk the cinnamon filling ingredients together and set aside.
A glass bowl with a spoon and streusel topping in it.
  1. Step 2: Melt the butter for the streusel, mix with the remaining streusel ingredients, and chill until firm. If it clumps, break it apart before topping the cake.
A large glass bowl with butter and mashed banana in it.
  1. Step 3: Melt the butter in a large bowl and whisk in the mashed bananas until combined.
A large glass bowl with a whisk and banana bread batter.
  1. Step 4: Whisk in the sugars, then add sour cream, vanilla, and eggs. The batter will be slightly lumpy due to the banana—this is normal.
A large glass bowl with a rubber spatula and banana bread batter.
  1. Step 5: Add the dry ingredients and fold with a rubber spatula until just combined—stop when no streaks of flour remain.
A square baking pan lined with parchment paper and filled with cake batter, topped with streusel.
  1. Step 6: Pour half of the batter into an 8×8-inch pan lined with an overhanging parchment sling. Sprinkle the cinnamon filling over the batter, then add the remaining batter and top with the chilled streusel. Bake until a toothpick comes out with little to no crumbs.
A slice of banana bread coffee cake drizzled with a white glaze on a small plate.

Top Tips from My Kitchen

  • Streusel: If the streusel clumps in the fridge, break it apart with a fork or your hands before sprinkling over the cake.
  • Weigh Ingredients: For best results and consistent baking, use a kitchen scale and measure by grams when possible.
  • Line the Pan: Use parchment that overhangs on two sides to create a sling so you can lift the cake from the pan easily after it cools.
  • Baking Time: This is a relatively thick cake and oven accuracy varies. Start checking at the minimum time, then add a few extra minutes as needed. Allow the cake to rest in the pan for about 20 minutes before transferring to a wire rack to cool completely.
A slice of banana bread coffee cake drizzled with a white glaze on a small plate.

More Recipes to Use Ripe Bananas

  • A close up of a slice of pecan banana bread on parchment paper.
    Brown Butter Cinnamon Banana Bread with Pecans (One Bowl)
  • A stack of two banana coffee cake muffins, one has a bite taken out of it.
    Banana Coffee Cake Muffins with Cinnamon Streusel
  • Banana mini muffins on a small plate.
    Banana Mini Muffins
  • Banana muffins in a pile, one with a bite taken out of it.
    Bakery Style Chocolate Chunk Banana Muffins
Ella from Alpine Ella is holding a cake stand with cupcakes on it.

Made This Recipe?

If you try it, please leave a rating and a review. Tag the author on Instagram @alpineella to share your photos.

Thank you!

Ella

Recipe

A close up of banana coffee cake, drizzled with a white glaze.

Easy Banana Coffee Cake with Sour Cream

Ella Gilbert

This banana coffee cake is ultra-moist with a cinnamon swirl and buttery streusel topping—no mixer needed. Perfect for ripe bananas.
Prep Time 20 mins
Cook Time 45 mins
Total Time 1 hr 5 mins
Course Breakfast, Dessert, Snack
Cuisine American
Servings 9 slices
Calories 459 kcal

Equipment

  • 8×8 baking pan
  • Kitchen scales (recommended)
  • 2 small bowls
  • 1 large bowl
  • Whisk
  • Rubber spatula

Ingredients

Cinnamon Filling

  • ½ cup (100 grams) brown sugar
  • 1 tablespoon ground cinnamon
  • 1 teaspoon cocoa powder

Cinnamon Streusel

  • ¾ cup (90 grams) flour
  • 6 tablespoons (85 grams) butter, melted
  • ¾ cup (150 grams) sugar
  • ¼ teaspoon kosher salt
  • ½ tablespoon cinnamon

Banana Cake

  • ½ cup (113 grams) unsalted butter, melted
  • 1 cup (250 grams) mashed bananas
  • ½ cup (104 grams) light brown sugar
  • ¼ cup (50 grams) white sugar
  • 2 teaspoons vanilla extract
  • 2 large eggs, room temperature
  • ¼ cup (56 grams) sour cream
  • 1 teaspoon baking soda
  • ½ teaspoon baking powder
  • ½ teaspoon ground cinnamon
  • ½ teaspoon kosher salt
  • 1 ¾ cups (210 grams) all-purpose flour
  • ¼ teaspoon ground nutmeg
Ella’s Baking Tip!
Weigh your ingredients with a kitchen scale for the best results.

Instructions

  1. Preheat the oven to 350°F (175°C). Grease and line an 8×8-inch baking pan with parchment paper, leaving an overhang for easy removal.
  2. Whisk the filling ingredients together: ½ cup brown sugar, 1 tablespoon cinnamon, and 1 teaspoon cocoa powder. Set aside.
  3. For the streusel, melt the butter and combine with ¾ cup flour, ¾ cup sugar, ¼ teaspoon kosher salt, and ½ tablespoon cinnamon. Chill until firm; break into small pieces before using.
  4. Melt ½ cup unsalted butter in a large bowl. Stir in 1 cup mashed bananas.
  5. Add ½ cup light brown sugar and ¼ cup white sugar; whisk for 1 minute.
  6. Whisk in 2 eggs, ¼ cup sour cream, and 2 teaspoons vanilla until nearly smooth; small lumps from the banana are fine.
  7. Fold in the dry ingredients: 1 ¾ cups all-purpose flour, 1 teaspoon baking soda, ½ teaspoon baking powder, ½ teaspoon ground cinnamon, ¼ teaspoon ground nutmeg, and ½ teaspoon kosher salt. Mix until no streaks of flour remain.
  8. Pour half the batter into the prepared pan, sprinkle the cinnamon filling evenly over it, then spread the remaining batter on top.
  9. Break the chilled streusel into pieces and scatter evenly over the top of the cake.
  10. Bake for 35–45 minutes, or until a toothpick inserted in the center comes out with little to no crumbs. Let cool in the pan for 20 minutes, then lift out using the parchment sling and cool completely on a wire rack.

Notes

These recipes are tested using metric weights. Using a kitchen scale yields the most consistent results. US cup conversions are provided but the recipe was developed with gram measurements.

Room temperature: For best results, bring ingredients to room temperature before starting—about 1–2 hours.

Salt: If you don’t have kosher salt, halve the amount called for. (For reference, 1 teaspoon Diamond Crystal kosher salt ≈ ½ teaspoon fine salt; different kosher salts vary in salinity.)

Sour cream: Full-fat yogurt can be substituted for sour cream if needed; avoid low-fat or nonfat swaps to preserve texture.

Storage: Store the cake wrapped tightly or in an airtight container. It will keep up to 3 days at room temperature or up to a week refrigerated.

Calories: 459 kcal
Carbohydrates: 81 g
Protein: 6 g
Fat: 13 g

The provided nutritional information is an estimate per serving. Accuracy is not guaranteed.

Tried this recipe?
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