Preheat broiler. In a large mixing bowl, whisk eggs and 1/2 of the cheese in a large bowl. Season with salt and pepper. Heat oil in a 10-inch ovenproof skillet over medium heat. Add garlic and sauté until fragrent, 1 or 2 minutes. Add mushrooms and asparagus; sauté until tender, about 5 minutes. Add egg mixture and stir to combine. Reduce heat to low, cover and cook until eggs are almost set, about 5 minutes. Sprinkle with remaining 2 tablespoons cheese. Transfer to broiler. Broil just until set in center, about 1 minute. Serve hot, warm or cold. Serves 4 to 6.