Start by getting all your ingredients in order. Peel and chop 1 large Russet or Yukon gold potato into ½-inch pieces, slice or dice 1 small yellow onion, chop 1 stalk of green onion and separate light and dark green pieces, mince 1-2 cloves garlic, large dice 1 ½ cups of ham, and shred 1 ½ cups cheddar cheese.

In a mixing bowl, whisk 8 large eggs and ¼ cup half-and-half until fully combined. Add the dark green part of the green onions, 1 tablespoon finely chopped parsley, 1 teaspoon finely chopped thyme, about ½ the salt and pepper, and whisk again until thoroughly mixed. Finally, stir in about 1 cup of shredded cheddar and set aside.

Preheat your oven to 350°F / 180° C.

Starting on the stove in a 12-inch skillet or other oven-safe pan, melt the butter and add the oil over medium-high heat. Season the potato and onion with some salt and pepper and sauté until mostly cooked through, about 10 minutes.

Once the onions are translucent and the potatoes are mostly cooked, add the ham and light parts of the green onion. Turn the heat down to medium-low and continue cooking and tossing for about 2-3 minutes longer. Add the minced garlic and cook until fragrant, for about 1 more minute.

Now spread the ingredients in the pan into an even layer, give the egg mixture a quick stir, and pour it over the ingredients in the skillet/pan. Cook for about 2-3 minutes until the bottom starts to set.

Top the frittata with the rest of the cheese and transfer the whole dish to the oven. Let it bake for 10-14 minutes, until fully set and cooked on top. It should be lightly browned and just barely jiggle in the center.

Remove it from the oven and let it cool and finish setting in the skillet for a few minutes. When ready to serve, it should slide right out of the pan. Slice and serve while still hot or warm.