Preheat oven to 350 degrees F and line mini muffin tins with liners.
In a medium-sized bowl, mash the bananas and combine with the lemon juice.
Add the melted butter, sugars egg and milk to the banana mixture and whisk until combined. Set aside.
In another medium-sized bowl, whisk together the baking powder, baking soda, salt and flour. Then pour the wet banana mixture into the flour mixtures and gently mix with a spatula jus until combined. Fold in the sprinkles.
Use a portion scoop or 1 tablespoon measure to fill the muffin liners about ¾ of the way.
Bake on the upper baking rack for 8-10 minutes for mini muffins and 15-18 minutes for standard muffins, until lightly golden.
Remove from the oven, and let them cool in the pan for 5 minutes and then transfer to a cooling rack until fully cooled.