Preheat the oven to 400°F, and line a 12 cavity muffin pan with liners.
Whisk the flour, baking powder, baking soda, sugar, and salt. Set aside.
2¼ cup All-purpose flour, 2½ teaspoon Baking powder, ¼ tap Baking soda, ¼ teaspoon Salt, ¾ cup Sugar
In a separate bowl, lightly beat the eggs, then add the orange juice, melted butter, sour cream, orange zest, and vanilla extract. Mix well.
1 tablespoon Orange zest, ½ cup Orange juice, ½ cup Butter, 2 Eggs, 1 cup Sour cream, 1 tablespoon Vanilla extract
Add this mixture to the flour mixture. Using a spatula, fold the flour into the egg, and gently mix until all the flour is incorporated. DO NOT OVERMIX.
Using a large spoon or ice cream scoop, pour the batter into the lined muffin pan. fill up the cavities to the top.
Bake for 15-20 minutes or until a dome is shaped and the muffin tops are slightly golden. Let cool in the pan for 10 minutes, then transfer to the cooling rack.