Healthy Smash Cake (vegan, gluten-free, no sugar added)

0 Preheat oven to 350 degrees F. Grease three 4-inch pans with avocado oil or coconut oil. 
1 In a small bowl, make the flax egg by combining the ground flaxseed and water. Stir and set aside to thicken.
2 In a medium bowl, add the oat flour, baking powder, baking soda, salt, and cinnamon. Whisk until well combined. 
3 In a large bowl, add the mashed banana, applesauce, milk, vanilla extract, avocado oil, and flax egg. Whisk until well combined.
4 Add dry ingredients to the bowl with the wet ingredients. Stir with a spatula until just combined. Careful not to over mix. 
5 Pour batter into the 3 pans. Bake for 18-20 minutes, or until a toothpick inserted comes out clean. Let the cakes cool in the pan for 10 minutes, then carefully remove cakes from the pans and place on a wire rack to cool completely. 
6 Once cakes are cooled, make the coconut whip. Chill your metal mixer bowl in the fridge for 15-30 minutes. Open the cans and scoop out only the coconut cream. Save the water for something else like smoothies. Whip with the whisk attachment of your electric mixer or KitchenAid mixer until light and fluffy. Add vanilla extract and whisk again until fluffy. Place in the fridge until ready to use. Note, this makes a lot of coconut whip because I feel like one can might barely not be enough if you want a thicker layer of frosting. 
7 Assemble the cake. Use a serrated knife to level the tops right before you plan to assemble. Place one layer of cake on a plate. Scoop some coconut whip on top and smooth it out. Place another layer on top and more coconut whip. Then place the last layer on top and frost the entire cake with coconut whip. 
8 Be sure to chill the cake until you need it because coconut whip will melt in room temperature. Enjoy!