I highly recommend trying mini cupcake/muffin liners for easy cleanup since these can stick. If you don't have any liners, it's fine, just use olive oil to grease and give the muffin pans a light soaking in water after. If you have non-stick muffin trays, be sure to use a plastic spoon to scoop them out afterward.
1 C peanut butter
1 C whole wheat flour
1/3+C chocolate chips (depending on how sweet you really want it. This will be the main sweetness)
2T chia seeds (optional)
2T Cocoa powder
3/4 tsp vanilla
1/2 C shredded unsweetened coconut
1 large banana
1/2 C milk
Halved walnuts for garnishing tops
Pre-heat oven to 375.
Combine all ingredients and mix well. Pour in mini muffin pans (greased or with liners) and top with a halved walnut each.
Bake for around 14 minutes (for the first time, keep your eye on them. Everyones oven is different!)