Start by peeling and mashing four very ripe bananas in a large mixing bowl. You want them soft and mostly smooth, though a few chunks are fine. Add in the egg, vanilla extract, melted butter, and both sugars. Beat everything together using a spoon or hand mixer until you get a consistent, slightly fluffy mixture.

In a separate medium bowl, sift the flour to eliminate lumps and aerate it. Whisk in the salt, baking powder, baking soda, and cinnamon. This mix ensures even distribution of the leavening agents, which will help your muffins rise perfectly.

Slowly pour the dry ingredients into the wet mixture while gently folding with a spatula. Avoid overmixing, which can lead to dense muffins. Once combined, stir in the chocolate chips. At this point, you can also add extras like chopped walnuts or dried cranberries for texture and flavor variation.

Grease your muffin tin or line it with paper liners. Distribute the batter evenly into the 12 cups, filling each about ¾ full. Bake in a preheated oven at 400°F (200°C) for 15–20 minutes. The muffins should turn golden brown and spring back when lightly pressed. A toothpick inserted in the center should come out clean (unless you hit a melted chocolate chip!).

Let the muffins cool in the tin for 5 minutes before transferring to a wire rack. Serve warm for gooey chocolate chips, or let them cool completely and store in an airtight container for up to 3 days. These also freeze well—perfect for future cravings.