Heat the olive oil in a wide, oven-safe skillet on medium high. Once hot, add the potatoes. Cook, turning them periodically, until golden brown all over and fork tender, which will take 20 to 30 minutes. Adjust the heat to medium or medium-low, as needed, so that the oil is gently sizzling and the potatoes turn golden brown without burning.
While the potatoes cook, beat together the eggs, cream, chives, salt, and chili flakes.
Once the potatoes are tender, pour the eggs over them. Gently nudge the potatoes so that they’re in an even layer. Crumble the feta cheese over the top.
Transfer the pan to the oven and bake until the frittata is just set in the center, 15 to 20 minutes. Cool for about 10 minutes in the pan, then slide onto a cutting board, cut into wedges, and serve, garnished with additional chives and chili flakes.
Substitute about 3 cups roasted or air-fried potatoes for the home fries, if you wish.
If using leftover potatoes, an oven-safe nonstick pan works great. Otherwise, a heavy skillet, such as a cast-iron or stainless steel one works best for frying the potatoes.
Leftover wedges of frittata will keep for up to 3 days in an airtight container in the refrigerator.