Preheat the oven to 350F and line a standard muffin tin with 12 parchment or silicone baking cups. (I use these silicone cups.) In a large mixing bowl, combine all of the ingredients and stir well with a whisk to break up any clumps.
Divide the batter into the 12 baking cups, then bake at 350F for 25 to 30 minutes, until the edges are golden and the centers are firm. Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.
Store the muffins in a sealed container in the fridge for up to one week, or in the freezer for up to 6 months.