01 -
Preheat the oven to 375°F. Line a 12-cup muffin pan with paper liners or grease the cups well.
02 -
In a large bowl, whisk together the flour, brown sugar, baking powder, baking soda, salt, cinnamon, and ginger until evenly combined.
03 -
In a medium bowl, whisk the eggs, buttermilk, oil, and vanilla until smooth.
04 -
Toss the chopped rhubarb into the dry ingredients so the pieces are lightly coated with flour.
05 -
Pour the wet ingredients into the dry ingredients. Fold gently with a spatula just until no dry flour remains. Do not beat the batter smooth.
06 -
Divide the batter evenly among the muffin cups, filling each about three-quarters full. Stir the granulated sugar and cinnamon together, then sprinkle it over the tops.
07 -
Bake for 18-20 minutes, until the tops spring back lightly and a toothpick inserted in a center muffin comes out with moist crumbs.
08 -
Cool in the pan for 5 minutes, then transfer the muffins to a wire rack. Serve warm or at room temperature.