Preheat the oven to 375 degrees F.
In a medium bowl, beat the eggs, Romano, milk, 1/2 teaspoon salt and 1 pepper with a whisk.
In a 12-inch nonstick skillet with an oven-safe handle, melt the butter on medium-high heat. Stir in the asparagus and the remaining 1/4 teaspoon salt, and cook 4 minutes. Add the green onions, and cook 2 minutes, stirring often. Spread the vegetable mixture evenly in the skillet.
Reduce the heat to medium-low. Pour the egg mixture into the skillet and cook without stirring until the mixture starts to set around the edge, 4 to 5 minutes. Place the skillet in the oven and bake until set, about 10 minutes. Invert the frittata onto a serving plate and cut into wedges.
Cook's Note: This recipe is higher in saturated fat. Choose other meals lower in saturated fat for the rest of the day so you don't exceed your daily limit of 15 g.
Nutritional information per serving: about 253 calories, 18 g protein, 5 g carbohydrate, 16 g total fat (7 g saturated), 1 g fiber, 443 mg cholesterol, 580 mg sodium