How to Make It
Dissolve yeast in 1 1/4 cups warm water in a small bowl; let stand 5 minutes.
Weigh or lightly spoon potato starch and flours into dry measuring cups; level with a knife. Combine potato starch, flours, xanthan gum, baking powder, and salt in the bowl of a stand mixer fitted with a paddle attachment; beat at medium speed until blended. Add yeast mixture, 3 tablespoons oil, 1 teaspoon rosemary, potato, and egg; beat until blended. Gently fold in olives and garlic.
Spoon batter into a large bowl coated with cooking spray. Cover with plastic wrap, and let rise in a warm place (85°), free from drafts, 45 minutes or until doubled in size.
Preheat oven to 400°.
Turn dough out onto a baking sheet coated with cooking spray; shape into an 11-inch round. Brush top of bread with 1 tablespoon oil. Sprinkle with 2 teaspoons rosemary and cheese. Bake at 400° for 35 minutes or until golden brown and loaf sounds hollow when tapped.