Spanish Potato and Onion Omelet

1 cup olive oil, divided
4 Yukon Gold potatoes, peeled and cut into 1/8-inch slices (about 4 cups)
salt, to taste
pepper, to taste
2 medium onions, thinly sliced (2-2 1/2 cups)
6 eggs
4 ounces cured, cooked ham or prosciutto, diced

In a large sauté pan, heat 3/4 cup olive oil. Cook half of the potatoes until tender and golden, turning often. Drain. Season with salt and pepper, to taste. Repeat with remaining potatoes. Add 4 tablespoons olive oil to pan. Cook onions until soft; about 15 minutes. Add potatoes to onions.

In a large bowl, beat eggs. Add eggs to potato and onion mixture. Stir in diced ham or prosciutto. Reduce heat to low and cook 8-10 minutes until golden brown on bottom. Invert platter on pan and flip omelet onto plate. Add remaining olive oil to pan; slide omelet back into pan. Cook until golden brown on bottom. Slide omelet onto serving plate. Let cool. Cut into wedges.
Recipe courtesy of the National Onion Association