Wash and thinly slice potatoes, leaving the skin on. Peel and slice onion. Put potatoes, onions and garlic in covered casserole dish. Drizzle with olive oil; sprinkle with salt and pepper. Lightly toss together to coat potatoes and onions.
Cover casserole and bake for 45 to 60 minutes or til potatoes are fork tender. Makes 4 servings.
For variety, add chopped rosemary, tarragon, or parsley.