Preheat your oven to 325°F and line 18 medium-sized muffin cups with paper liners.
In a small bowl, combine the graham cracker crumbs with the melted butter.
Place a heaping tablespoon of this mixture into each muffin cup and press it firmly to form a crust. Bake for 5 minutes, then remove and let the crusts cool.
While the crusts are baking, mix the cream cheese and granulated sugar until smooth.
Add the eggs, vanilla extract, and mashed bananas, stirring just until combined. Avoid overmixing.
Spoon about 3 tablespoons of the filling into each muffin cup, over the cookie crust. You can fill them nearly to the top since they won’t rise much, but leave a small gap for easy removal of the liners.
Bake at 325°F for 20 minutes. Afterward, turn off the oven, crack the door open, and let the cheesecakes sit in the oven for an additional 10 minutes.
Once out of the oven, let them cool at room temperature for at least 30 minutes before transferring them to the refrigerator to chill completely, for at least an hour.
Finish with an optional garnish of banana slices, or your favorite topping.