In large bowl, whisk together flour, baking powder, sugar, salt, and garlic powder. Using pastry blender or two knives, cut in butter until mixture resembles coarse crumbs with a few larger pieces.
Stir in cheese, green onions, rosemary, and pepper. Using fork, stir in milk to form a ragged dough.
Drop dough by ¼ cup, 1½ inches apart, onto parchment paper–lined cookie sheet. Bake in 425°F oven until lightly browned, 13–15 minutes.