This unassuming recipe has big flavor despite a short ingredients list. To save time, peel the onions up to 24 hours ahead.
Cook onions in rapidly boiling water for 1 minute; drain and cool slightly. To peel, cut a small X in top of onion. Squeeze from the root end to slip the skin off. Trim away the roots, if necessary.
In a large skillet cook onions, covered, in lightly salted boiling water for 10 to 12 minutes or just until tender; drain. Cover and chill up to 24 hours.
Let onions stand at room temperature about 30 minutes. In a large skillet melt butter over medium heat; stir in sherry, sugar, salt, and pepper. Add onions and cook over medium heat about 5 minutes or until onions start to brown and butter mixture is thickened, stirring occasionally. Turn into serving dish; sprinkle with cheese. Makes 8 servings.
Onions may be prepared without the chilling step.