- 1 1/2 cups all-purpose flour
- 1/4 teaspoon baking powder
- 1/8 teaspoon baking soda
- 1/2 cup butter, softened
- 1 cup white sugar
- 1 teaspoon vanilla extract
- 3 large eggs
- 1/2 cup sour cream
- 2 teaspoons grated orange zest
- 1 teaspoon chopped fresh rosemary
- Preheat oven to 325 degrees F (165 degrees C). Grease and lightly flour a 9×5-inch loaf pan.
- Whisk flour, baking powder, and baking soda together in a bowl.
- Beat butter in a bowl using an electric mixer until smooth and creamy, about 30 seconds. Gradually beat sugar into butter until light and fluffy; add vanilla extract and beat until incorporated. Beat eggs, 1 at a time, into creamed butter mixture, beating about 1 minute after each addition.
- Beat flour mixture, alternating with sour cream, into creamed butter mixture with the electric mixer on low until batter is just combined. Stir orange zest and rosemary into batter; pour into the prepared loaf pan.
- Bake in the preheated oven until a toothpick inserted into the center comes out clean, 60 to 70 minutes. Cool in the pan for 10 minutes before removing to cool completely on a wire rack.