Preheat the oven to 425°F (218°C). Line a 12 count muffin tin with paper liners or grease generously to prevent sticking.

Whisk together the dry ingredients, including the add-ins, in a large mixing bowl. Set aside.

In a medium mixing bowl, whisk the wet ingredients together until smooth. Pour the wet ingredients into the dry ingredients and stir until just combined. (If the batter is too stiff, add 1-2 tablespoons of water to help thin it down.)

Divide the batter evenly into 12 muffins. (At this point you can bake right away or allow the batter to ferment in the fridge overnight and bake the next day. See notes.)

Bake for 5 minutes at 425°F (218°C). Turn the oven down to 350°F (176°C) and bake an additional 18-20 minutes or until a toothpick inserted into the center of a muffin comes out clean. Let the muffins cool in the tin for 10 minutes before transferring them to a cooling rack.

Keep the muffins loosely covered, at room temperature, for up to 2 days or in the fridge for up to 1 week. After that they can be frozen, individually wrapped in plastic and then inserted into a freezer-safe container for up to 3 months.