1. Preheat oven to 350° with oven rack 6 inches from top of heat source. Snap off and discard tough ends of asparagus. Cut asparagus diagonally into 1-inch pieces. Melt butter in a 10-inch ovenproof skillet over medium-high heat; add onion, and sauté 3 to 4 minutes or until onion is tender. Add asparagus; sauté 3 to 4 minutes or until tender. Add garlic, and sauté 1 minute.
2. Whisk together eggs and next 3 ingredients until well blended. Stir in 3/4 cup Gouda cheese. Fold egg mixture into vegetable mixture in skillet. Cook, stirring occasionally, 2 to 3 minutes or until almost set. Sprinkle with Parmesan cheese and remaining 1/4 cup Gouda cheese.
3. Bake at 350° for 5 minutes or until set. Increase oven temperature to broil, and broil 3 to 4 minutes or until golden brown.