Frittata di Spinaci con Parmigiano e Funghi {Spinach & Portobello Frittata}

Preheat oven to 350 degrees. Crack the eggs into a bowl, add the milk, sun dried tomato and Parmigiano. Whisk together until well combined. Season with salt and pepper, set aside. Into a cast iron pan (or other oven safe pan) add the olive oil and onion and saute approx 2 minutes over medium heat. Stirring frequently. Add mushrooms, reduce heat to low and continue to stir while cooking until mushrooms have released their water. Add spinach and cook just until just wilted. Season with salt and pepper.

Pour egg mixture into pan and stir gently to combine. Allow to cook until the sides begin to set up. Transfer to oven and cook until eggs are no longer giggly. Approx 15 mins {check it every so often} Transfer to serving plate & enjoy immediately.