Smoked Ham, Gruyere, and Caramelized Onion Frittata

I had some gruyere cheese leftover from a mac and cheese I had made and found this recipe on Food Network. It was perfect for Easter Breakfast along with the Sparkling Punch and some Holiday Buns. It was really similar to a breakfast casserole but I thought the texture was much better. It looks like you spent a lot of time in the kitchen but in reality it comes together pretty quickly. I made sure to dice my potatoes really small so they would cook fast. I didn't bother with the sour cream on the side.

Ingredients
8 extra-large eggs (I used 9 large eggs)
2 tablespoons heavy cream
1 cup grated Gruyere cheese
Kosher salt and freshly ground black pepper
1 tablespoon unsalted butter
1 small onion, diced
4 small red potatoes, diced
1 cup diced smoked ham or Canadian bacon
1 cup grated Parmigiano-Reggiano, for finishing top
1/4 cup sour cream
1 bunch chives, chopped


Directions

Preheat oven to 400 degrees F.
In a large bowl, whisk together eggs, cream, Gruyere cheese, salt, and pepper until foamy. Melt butter in a cast iron pan over medium heat. Add the onion and potatoes and cook thoroughly. Pour the egg mixture over the top. Pull the edges away from the sides of the pan with a spatula so the eggs flow to the bottom of the pan. When the frittata is half set, add the ham.
Transfer the pan to the heated oven. Bake for 10 minutes until puffed and golden. Shower with grated Parmesan and serve garnished with sour cream and chives