Mix cheeses, spinach, mushrooms, pepper, garlic powder,  Italian herb seasoning, salt and egg in a medium mixing bowl.

Roll bread dough into a 16 x 10-inch rectangle on a lightly floured surface. Spread spinach mixture over dough leaving a 1/2-inch border. Roll up lengthwise, jelly roll style; pinch seam and edges to seal.

Place roll diagonally on a greased baking sheet. Cut 6 slits into top of roll using a sharp knife. Brush with olive oil. Cover and let rise in a warm place, about 45 minutes or until double in size.

Bake at 350º F for 30 minutes or until golden.