Banana Marble Muffins

1. Preheat oven to 375 F. Grease a 12-count standard size muffin pan with cooking spray.
2. In a large bowl, mix together the mashed bananas, oil, applesauce, eggs, sugar, and vanilla.
3. In another bowl, mix together the all-purpose flour, cinnamon, baking powder, baking soda, and salt.
Mix the dry ingredients with the wet ingredients.
4. In a microwave-safe bowl, heat the chocolate chips for a minute and check them. Continue microwaving the chips in 20-second increments until all the chips have a glossy sheen. Stir the chocolate together until you get a thick chocolate sauce. Mix this melted chocolate with 1 cup of the muffin batter.
5. Pour a layer of the banana batter into all of the tins, then top it with a chocolate layer. Continue alternating layers until all the muffin tins are full with the batter. I made the top layer half-banana and half-chocolate. Run a toothpick through the top to create a swirl pattern.
6. Bake the muffins for 22-25 minutes or until a toothpick inserted in the center of one comes out clean.
7. Store any leftovers at room temperature in an airtight container.