2 tablespoons ground flaxseed (or start with 1 tablespoon whole seeds and grind them yourself)
2 cups flour
1/2 cup rolled oats, finely ground in the food processor (or 1/3 cup additional flour)
3/4 cup sugar
1 tablespoon baking powder
1 teaspoon baking soda
1/4 teaspoon salt
1 navel orange, organically grown*
1 cup almond or other non-dairy milk
1/3 cup vegetable oil
Coarse sugar for sprinkling (optional)
*The peel of the orange needs to be free of bitter pesticide waxes. You can try using a conventionally-grown orange and scrubbing it with soap and water to remove the wax, but I've ruined enough dishes with bitter lemon and orange peels from conventional fruit that I wouldn't recommend it.
Preheat oven to 400 degrees F. Line a 12-cup muffin tin with paper liners. You may want to prepare a few extra cups; I made 15 smaller muffins.
In a small mixing bowl, mix the ground flaxseeds with 3 tablespoons hot water. Stir with a fork until thickened.
In a large mixing bowl, stir together the flour, ground oats, sugar, baking powder, baking soda, and salt until thoroughly combined.
Cut the orange into eights, remove any seeds, and purée it in a food processor. Add to the flaxseed mixture in the small bowl, then add the milk and oil. Pour this over the dry ingredients in the large bowl and fold just until combined.
Fill muffin cups about 3/4 full for 15 smaller muffins, or divide all the batter among 12 cups (they will spill over the edges). Sprinkle each muffin, if desired, with a little coarse sugar (I find fingertips are the best way to do this sparingly). Bake for 18-20 minutes, or until tops are golden and a toothpick comes out clean. Remove to a rack and cool completely before eating.