Preheat the oven to 350 °F. Lightly spray a 12-cavity muffin pan with nonstick spray.
In a large bowl, whisk together the flour, cornmeal, ground flax, brown sugar, cinnamon, baking powder and salt.
In another bowl, beat the egg with a whisk. Whisk in the skim milk and oil.
Pour the egg/milk/oil mixture into the flour mixture and stir with a spoon until fully incorporated.
Spoon the batter into the muffin tin. A ¼-cup measuring cup or an ice cream scoop work well.
Bake the muffins at 350 °F for 20 minutes or so. Muffins are done when the tops are golden-brown. A toothpick inserted into the center of each muffin will come out clean.