Preheat oven to 400 degrees. Grease 12 muffin cups, or line with muffin papers.
Combine flour, baking powder, 3/4 teaspoon cinnamon, cloves, nutmeg and salt in a bowl. In a separate bowl, beat egg with sour cream, butter and orange juice. Stir in orange zest and brown sugar and mix well.
Add sour cream mixture to dry ingredients and stir until just combined. Fill prepared muffin cups about 3/4 full. Combine sugar with remaining 1/2 teaspoon cinnamon and sprinkle over muffins.
Bake in preheated oven for 20 to 25 minutes, or until lightly browned and springy to touch. Allow muffins to stand for 5 minutes before turning them out onto a wire rack to cool slightly. Serve warm. Makes 12 muffins. Enjoy!