Preheat oven to 350 degrees Fahrenheit. Spray an 8 by 8 in square pan for cake or a muffin tin for chocolate chip muffins with nonstick spray. In a food processor, puree a medium to large banana until smooth. In a small bowl, melt 1 stick of butter.
Measure all dry ingredients into a large mixing bowl, and mix with a whisk until all ingredients are thoroughly mixed together.
Add pureed banana, melted butter, eggs, molasses and mix well with a spatula until the mixture is homogeneous and smooth.
Stir in raisins or chocolate chips, whichever you have chosen.
Bake at 350 degrees until the cake bounces back when touched and is a golden brown. This should be around 17 minutes for muffins and 25 minutes for the cake. Every oven varies slightly so feel free to check with a toothpick.
Once the cake is done, wait until completely cooled before removing from the pan.*
Place the cake on a cooling rack over a sheet pan, and drizzle the glaze over top.
Let glaze set and then enjoy.