Prepare the filling first if you are using it. With a hand mixer or stand mixer, beat vegan cream cheese and sugar in a bowl until fluffy and smooth. Place in the fridge while you prepare the muffins
Muffins
Preheat oven to 375°F. Line a 12-cup muffin pan.
Add bananas to a large mixing bowl and mash with a fork.
Coarsely grate carrots on the large holes of a grater. Add to bananas.
Add sugar, molasses, almond butter, vinegar, milk, ground flax, and vanilla extract. Mix until well combined.
Add whole wheat flour, cinnamon, and nutmeg. Sift baking soda on top. Use a spatula to fold the batter together just until no dry flour pockets remain.
Add walnuts and raisins and fold a couple times to distribute in the batter.
Divide the batter among the muffin cups. If you want to add a cream cheese filling, fill the muffin cups up halfway, add a spoonful of cream cheese filling, and add the remaining batter on top.
Bake 23-25 minutes until a toothpick inserted in the center of a muffin comes out clean.