Preheat oven to 350 F. Line a 12-cup muffin tin with paper liners or grease with nonstick cooking spray.
In a medium mixing bowl, combine flour, ginger, cinnamon, baking powder, baking soda, and salt. Set aside.
In a separate large bowl, whisk together oil and brown sugar.
Whisk in molasses.
Add egg, and whisk to combine.
Add buttermilk; whisk until well-combined.
Add flour mixture, and whisk until just combined.
Scoop into muffin cups. The cups will be full.
Sprinkle the tops with coarse sugar, if using.
Bake for about 20-25 minutes, or until when a toothpick inserted in the middle comes out clean.
Video
Notes
Flour: Be sure to either weigh the flour or aerate, spoon, and level it. You can find the weights for the ingredients by clicking on "metric" immediately above the ingredients.
Oil: I've used melted coconut oil, mild olive oil, and vegetable oil in this recipe.
Brown sugar: You can use light brown sugar if you don't have dark brown sugar.
Molasses: Mild or robust molasses is ok. I don't recommend blackstrap.