Preheat your oven to 375°F (190°C).
Sauté asparagus and peas in olive oil over medium heat for 3–4 minutes until just tender. Add spinach and cook until wilted.
Whisk together eggs, milk, salt, and pepper in a bowl.
Stir in the cheese and pour the mixture over the vegetables in the skillet.
Cook on the stovetop for 2–3 minutes, then transfer the skillet to the oven.
Bake for 15–18 minutes or until the eggs are set and the top is lightly golden.
Cool slightly, then slice and serve warm or at room temperature.