The first is to mix the dry ingredients. In a bowl, combine the flour, salt, baking soda, and sugar. After whisking the ingredients together, set the bowl aside.
Next, combine the wet ingredients. In a bowl, mash the bananas, then mix in the egg, melted butter, and vanilla. Add chocolate chips.
Then, using a spatula, fold together the dry and wet ingredients. Continue mixing until the chocolate chips are evenly distributed into the batter.
Prepare a muffin tray with liners and preheat the oven to 375 degrees Fahrenheit.
Scoop the batter into the prepared muffin cups, and sprinkle with more chocolate chips.
Bake for 17–20 minutes, or until a toothpick inserted into the center comes out clean.