Marble Banana Bread With Streusel Topping

Streusel topping

Combine 1/2 cup flour, 1/4 cup packed brown sugar, 3 Tbsp granulated sugar, and 1/4 tsp salt.

Pour in 1/4 cup of melted, cooled butter, then delicately stir with a fork until you've got a mix resembling wet sand, studded with pea-sized chunks. The key here is not to overdo it—keep those buttery bits intact! It's your ticket to crumbly goodness.

Banana Bread

Preheat oven to 350 F / 175 C and grease an 8.5 in x 4.5 in loaf pan with non-stick spray or butter and line with a sling of parchment paper.

Add 1/4 cup unsalted butter and 1/2 cup granulated sugar into a large bowl. Beat on a medium-high speed for a couple of minutes with either a hand mixer or a stand mixer with a whisk attachment. Beat until the mixture becomes lighter in color and looks fluffier.

Mix in 1/4 cup vegetable oil and 1 large, whole egg + 1 egg white on a medium speed. Scrape the sides and bottom of the bowl as needed with a rubber spatula.

Add 1 1/4 cups of all-purpose flour, 1 1/2 tsp baking powder, 1/2 tsp baking soda, and 1/2 tsp salt. Mix on a low speed until just combined. Pour in 1/2 cup of buttermilk and mix on a low speed until incorporated.

Mash 2 large, overripe bananas and mix 1 cup of mashed bananas into the batter on a low speed until just combined.

Divide the batter evenly between two bowls (about 400g per bowl). Mix 1/4 cup of cocoa powder into one bowl, and 1/4 cup of all-purpose flour into the other bowl. Stir until just combined.

Alternate spoonfuls of regular and chocolate batter into the prepared pan, then gently swirl the batter together with a butter knife. Cover the top of the batter with an even layer of chocolate chip streusel.

Bake on the middle baking rack for 60-70 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs. Rotate the pan halfway through to make sure it bakes evenly. If you notice the streusel on top of the loaf is over-browning when you rotate it, cover the loaf pan with a foil tent to prevent it from over-browning.