In a large mixing bowl, whisk together flour, sugar, baking powder, baking soda, and salt until no lumps remain.

In a separate bowl, whisk together eggs, buttermilk, vegetable oil, orange zest, and orange juice until well combined.

Gradually fold wet ingredients into dry ingredients using a spatula, mixing until just combined.

Cover bowl with a kitchen towel and let batter rest at room temperature for 15 minutes.

Preheat oven to 425°F and line a muffin pan with 6 paper liners, filling every other liner.

Fill each liner to the brim with muffin batter and bake for 7 minutes at 425°F.

Reduce temperature to 350°F and bake for an additional 13 to 16 minutes, checking for doneness.

Allow muffins to cool in the pan for 5 minutes before transferring to a wire rack.

Mix powdered sugar and orange juice for the glaze, and drizzle it over cooled muffins if desired.