In a 10-in. ovenproof skillet, saute onion and rosemary in 1 tablespoon butter until tender. Add garlic; cook 1 minute longer. Remove from the pan and set aside. In the same skillet, cook potatoes in 2 tablespoons butter until tender and golden brown. Remove and keep warm.
In a large bowl, whisk the eggs, milk, salt and pepper. Stir in cheese and onion mixture. Melt remaining butter in the skillet; tilt pan to evenly coat. Add egg mixture. Bake at 350° for 8-10 minutes or until nearly set.
Top with potatoes; bake for 3-5 minutes or until eggs are completely set. Let stand for 5 minutes. Cut into wedges. Yield: 4 servings.