First, set your oven to preheat at 350°F (180°C). Grab a 9x13 inch baking pan and lightly spray it with non-stick spray. Prep work is key—this step is where the magic starts.

In a mixing bowl, sift together the flour, white granulated sugar, brown sugar, baking powder, baking soda, salt, ground cinnamon, and nutmeg if using. Give them a good stir to ensure they’re combined. This mix will create a beautiful bed for our wet ingredients.

Now, let’s make the vegan buttermilk. In a measuring jug, combine 1 tablespoon of lemon juice with soy milk until it reaches the ⅔ cup (160ml) line. Give it a little stir and let it sit for at least one minute to curdle. This simple trick adds moisture to the cake.

In a blender, add the ripe bananas, your homemade vegan buttermilk, and melted coconut oil. Blend these goodies briefly until they’re just combined. Be careful not to overblend. We want bits of banana to remain for texture!

Pour the banana mixture over the dry ingredients and gently fold them together. This creates a batter that’s lively and fluffy.

Next, we’ll prepare the flax egg by mixing 1 tablespoon of ground flaxseed meal with 3 tablespoons of hot water. Let this sit for about a minute until it forms a gel-like consistency.

Fold the flax egg, unsweetened applesauce, and vanilla extract into your batter. Give it a gentle whisk with a hand whisk to break up any lumps. The batter should be thick and slightly pourable when you’re done—just the right consistency.

Pour your batter into the prepared baking pan, spreading it out to an even layer. Slide that pan into your preheated oven and bake for around 40 minutes or until a toothpick poked in the center comes out clean. Your kitchen will start smelling divine!

Once the cake is done, take it out of the oven and place it on a cooling rack. Give it time to cool completely before frosting. Trust me, it’s worth the wait.

While your cake cools, let’s whip up that lemon frosting. In a stand mixer, combine the powdered sugar, vegan butter, and 2 tablespoons of freshly squeezed lemon juice. Start mixing on low speed and gradually increase until you reach a thick, creamy consistency. If the frosting is too thick, add a drop of lemon juice at a time until you achieve your desired consistency.

Once the cake is completely cool, frost the top generously with your lemon frosting. To finish, sprinkle some crushed walnuts on top for a pop of flavor and texture.