Make flax “eggs” and refrigerate for 10 min to thicken.
Whisk together dry ingredients in a bowl with exception of 3/4 cup chocolate chips and 1/2 cup chopped nuts.
In a separate bowl, whisk together all wet ingredients (mashed banana through vanilla extract) or use a hand mixer. Slowly add dry ingredients until it forms a smooth batter. Stir in 3/4 cup of chocolate chips and chopped nuts.
Pour batter into a parchment paper lined 9 x 13 pan. Use a spatula to evenly spread. Bake for 35-38 minutes.
Cool completely before frosting with Simple Mills Vanilla Frosting. Finish with sprinkles (if desired)!