Easy Banana Cake with Chocolate Drizzle

This Easy Banana Cake is soft, moist, and perfect for using up ripe bananas. Sour cream keeps the crumb tender, while a little fresh lemon zest adds a subtle brightness that balances the natural sweetness of the fruit.

The cake is simple enough for an everyday bake but gets a lovely finishing touch from dark and white chocolate drizzled over the top. It is delicious with a cup of coffee or tea and makes an easy homemade treat for the whole family.

Servings: 8-10 - Prep: 20 min - Cook: 35-40 min - Total: About 1 hour + cooling

Ingredients

For the Banana Cake

• 130 g granulated sugar (about ⅔ cup)

• 60 g unsalted butter, softened (4 tbsp + 1 tsp)

• 2 large eggs, at room temperature

• 200 g ripe banana, peeled and mashed (about ¾ cup + 1 tbsp)

• 80 ml milk (⅓ cup)

• 90 g sour cream (about ⅓ cup + 1 tbsp)

• 180 g plain flour (1½ cups all-purpose flour)

• 1 tsp baking powder

• ½ tsp bicarbonate of soda (baking soda)

• Zest of ½ lemon

For the Chocolate Drizzle

• 40 g dark chocolate

• 20 g white chocolate

Instructions

1. Prepare the Oven and Tin

Preheat the oven to 180°C conventional / 160°C fan / 350°F. Grease your cake tin with butter and line with baking paper.

2. Prepare the Banana

Peel the ripe bananas and mash them thoroughly with a fork until mostly smooth. A few very small pieces are fine, but there should not be any large chunks. Very ripe bananas with plenty of brown spots will give the cake the best sweetness and banana flavour.

3. Cream the Butter and Sugar

Place the softened butter and granulated sugar in a large mixing bowl. Using an electric hand mixer, beat for approximately 2-3 minutes, until lighter in colour and creamy. Scrape down the sides of the bowl when necessary.

4. Add the Eggs

Add the eggs one at a time, mixing well after each addition. Using room-temperature eggs helps them combine more easily with the butter mixture. If the mixture looks slightly curdled after adding the eggs, don't worry—it will come together once the flour is added.

5. Add the Banana

Add the mashed banana and mix until well incorporated.

Continue mixing briefly until the banana is evenly distributed and the mixture looks creamy.

Avoid beating for too long.

6. Add the Milk and Sour Cream

Pour in the milk and add the sour cream. Mix on low speed until smooth and evenly combined. The sour cream helps keep the cake soft and moist after baking.

7. Add the Dry Ingredients

Sift the plain flour, baking powder, and bicarbonate of soda directly into the bowl. Add the finely grated lemon zest. Fold everything together gently using a spatula, or mix briefly on the lowest speed. Stop as soon as no visible flour remains. Do not overmix the batter, as this can make the cake heavier and less tender.

8. Fill the Tin

Pour the cake batter into the prepared tin. Spread it gently into an even layer and smooth the surface. Tap the tin lightly on the worktop once to release any large air bubbles.

9. Bake

Bake in the preheated oven for 35-40 minutes. Begin checking the cake after 35 minutes. The cake is ready when the top is golden, the centre springs back lightly when touched, and a skewer inserted into the middle comes out clean or with a few moist crumbs. If there is wet batter on the skewer, bake for a few more minutes and check again.

10. Cool

Leave the cake in the tin for approximately 15 minutes. Carefully remove it from the tin and transfer it to a wire rack. Allow the cake to cool completely before adding the chocolate drizzle.

Chocolate Drizzle

11. Melt the Dark Chocolate

Break or finely chop the dark chocolate and place it in a microwave-safe bowl. Microwave for 15-20 seconds at a time, stirring well between each interval, until almost completely melted. Stop heating while a few small pieces remain and continue stirring until completely smooth. This helps prevent the chocolate from overheating.

Alternatively, melt the chocolate gently in a heatproof bowl placed over a saucepan of barely simmering water, making sure the bowl does not touch the water.

12. Drizzle the Dark Chocolate

Using a small spoon or piping bag, drizzle the melted dark chocolate over the completely cooled cake. Move the spoon backwards and forwards to create thin lines across the surface.

13. Melt the White Chocolate

Melt the white chocolate separately. White chocolate is more sensitive to heat, so microwave it in short 10-15 second intervals, stirring thoroughly each time. Stop heating as soon as it is smooth.

14. Add the White Chocolate

Drizzle the melted white chocolate over the dark chocolate. You can make thin lines in the same direction for a simple finish or drizzle them in the opposite direction to create a contrast. Leave the chocolate to set before slicing the cake.

Tips and Tricks

✅ Use very ripe bananas with brown-speckled skins for the sweetest flavour and softest cake.

✅ Weigh the peeled banana if possible. Too much banana can make the centre of the cake heavy or overly wet.

✅ Bring the butter and eggs to room temperature before starting so they combine more smoothly.

✅ Add the eggs one at a time to help prevent the mixture from splitting.

✅ Sour cream gives the cake extra moisture and helps keep the crumb tender.

✅ Finely grate only the yellow part of the lemon peel and avoid the bitter white pith underneath.

✅ Once the flour has been added, mix only until combined. Overmixing can make the cake dense.

✅ Begin checking the cake after 35 minutes rather than relying only on the baking time, as ovens can vary.

✅ Let the cake cool completely before adding the chocolate. Chocolate drizzled over a warm cake will melt and run.

✅ Melt white chocolate particularly gently because it can overheat and seize more easily than dark chocolate.

✅ For thin, neat chocolate lines, transfer the melted chocolate to a small piping bag and cut only a tiny opening at the tip.

✅ You can use only dark chocolate if you prefer a simpler finish, or leave the chocolate off completely for an easy everyday banana cake.