Let refrigerated pie crusts come to room temperature; cut with 3-inch round biscuit cutter or glass. Press crust circle in each of 24 small muffin cups, 1 3/4x1 inch.
Melt butter in 10-inch skillet over medium-high heat. Cook 3/4 cup onion in butter 5 minutes, stirring occasionally; reduce heat to medium. Cook about 15 minutes longer, stirring occasionally, until onion is softened and golden brown; remove from heat.
Heat oven to 400º. Beat eggs in large bowl. Stir in sour cream, salt and pepper sauce. Stir in onion. Stir in 1/4 cup of the cheese. Spoon onion mixture into crusts. Sprinkle with remaining cheese.
Bake 10 to 15 minutes until golden brown and set in center. Serve warm or at room temperature. Garnish with additional onion.