simmer the beans in water for 40–60 minutes (until soft)
drain and add maple syrup
cook on low for 2–3 minutes so most of the liquid goes away while it cools
remove from heat
Preheat oven to 350°F
Line a muffin tin with paper liners
Make the batter
In a small mixing bowl whisk together the dry ingredients
In a medium mixing bowl
whisk together the egg and sugar and oil until light
whisk in the sour cream
mix in the beans
Add the dry to the wet and fold with a spatula or bowl scraper until just combined
Bake
Divide batter into the prepared cups using a sorbet scoop
Bake at 350°F until set, ~25 minutes
Cool on a wire rack
Notes
The recipe I started with used butter and milk instead of oil and sour cream, but the texture from these two changes is way better. Next to try is greek yogurt instead of sour cream.