5-6 ripe bananas, smashed (the browner the better. I usually just put them in the stand mixer, fitted with the paddle attachment, then turn it on medium until there is mostly banana goo with a few little chunks)
3/4 cups sour cream
3/4 cup Nutella or peanut butter (or any combination of both)
4 large eggs
1/2 cup melted butter, cooled to lukewarm
2 tsp vanilla
1 cup brown sugar, lightly packed
1 cup granulated sugar
(those last two aren't wet, but they get mixed with the wet before the dry goes in)
(In a large mixing bowl, sift/whisk together the following:)
3 1/2 cups all-purpose flour
1 tsp salt
2 tsp baking soda
1-2 tsp cinnamon
1/2-1 tsp nutmeg
1 1/2 cups chocolate chips (any sweetness - I prefer semisweet), set aside
This can be done in one muffin tin. I prefer to use two, because otherwise it feels like you're doing nothing but lining and filling for 2 hours. So, line two muffin tins with paper or foil liners. Pre-heat oven to 350 degrees.
In the bowl of your stand mixer, fitted with the paddle attachment, add the banana, sour cream, and Nutella/peanut butter and mix until well combined. Add eggs, one at a time, and mix until well combined. Add sugars, butter and vanilla and mix again.
Make a well in the bowl of your dry ingredients, then dump the wet ingredients in the center. With a rubber spatula, fold the wet ingredients into the dry ingredients until just incorporated. Do not over-mix. Add the chocolate chips and fold again.
Fill muffin cups until about half full. Bake (one pan at a time) at 350 degrees 18-22 minutes, or until a toothpick inserted into the center of one of the middle muffins comes out clean or with a few crumbs. Cool slightly in the pan (only until cool enough to quickly handle...think "hot potato"), then transfer muffins to a wire rack to cool completely. This recipe yields a LOT of muffins (about 40). Place any leftovers in freezer-safe containers (I use gallon size Ziploc bags) and store in freezer. They're good for a few days (2 or 3) when kept covered, and they freeze beautifully. I would guess they'll keep in the freezer for a few months, but ours never last more than a couple of weeks.