I hope this is still in time. I read the challenge when it was posted, was all excited about it and then promptly forgot all about it until the call for entries was posted. Then, of course, I couldn't find decent bananas anywhere.
Finally everything fell into place yesterday, so here's my recipe.
I came up with it when I had bananas that were almost too far gone, and needed to make something, but couldn't find one recipe that matched the ingredients I had at home. So, I combined ideas from different recipes, and when it turned out well, scribbled the recipe in my notes.
ingredients:100gr butter (softened a bit)
1 cup sugar (I used light brown)
2 eggs
2 cups self-rising flour
1 teaspoon baking powder
3 bananas (or 2 very large ones, about 1 cup when mashed)
some chocolate chips (about 2 scoops, I just put enough to have a few in every muffin)
The ingredients gathered up:

1. preheat oven to 180 degrees Celsius (around 350F)
2. mix the butter and sugar
3. add the following one ingredient at a time: eggs, bananas, flour and baking powder, and finally the chocolate.
After the flour is added try to do as little mixing as possible, I always read to mix just until everything is combined to avoid having banana mini bricks instead of fluffy muffins.
The batter looks like this:

4. scoop about a spoon into lightly oiled muffin pans

5. place in oven and bake for about 15-20 minutes, until muffins have browned

6. Take out of pans and place on cooling rack (careful when taking them out of the pans, hot hot hot)
These are best eaten right after they have cooled, they have a lovely outer crust, but no one ever complained when eating them the day after I baked them. You can also prepare the batter the day before and then just scoop into the pans and pop into the oven for a quick treat to take to work (that's what I do, my coworkers love seeing me show up the bag I use to carry them).
I have pans that have 15 cups each, and they yield nice mini muffins that are about 2 or three bites. The recipe yields about 45 mini muffins, or 12 regular sized muffins.
The chocolate chips can be omitted or replaced with pecans, or anything else that you like to combine with bananas.
Now I'm off to bake another batch. (then I'll come back to drool over all the other yummies on this board)