-
1
Preheat broiler.
-
2
Whisk together eggs, basil, parmesan, 1/4 teaspoon salt, and 1/4 teaspoon pepper in a large bowl.
-
3
Cook bacon in a 10-inch heavy skillet over medium heat, stirring, until crisp. Transfer bacon with a slotted spoon to a large bowl then pour off all but 2 tablespoons fat.
-
4
Add potatoes and 1/4 teaspoon each of salt and pepper to skillet, and saute over medium-high heat until golden, about 3 minutes. Cover skillet and continue to cook over medium-low heat, stirring a few times, until potatoes are just tender, about 3 minutes more. Transfer the potatoes with a slotted spoon to bowl containing the bacon.
-
5
Add 1 tablespoon oil to skillet and saute onion and garlic over medium-high heat until pale golden, about 4 minutes, then add spinach and saute until just wilted.
-
6
Gently add the potatoes and bacon, the roasted peppers, and remaining tablespoon oil into onion mixture, spreading it evenly.
-
7
Pour egg mixture evenly over vegetables and cook over medium-high heat, lifting up cooked egg around edges with a heat-proof rubber spatula to let uncooked egg flow underneath, 2 to 3 minutes. Reduce heat to medium and cook, covered, until it appears mostly set, with a moist top and center, 3 to 5 minutes more.
-
8
Remove lid. If using Provolone, broil frittata 5 to 7 inches from heat until set, but not browned, 1 to 2 minutes, then top with an even layer of cheese and continue to broil until browned and bubbling, 1 to 3 minutes (watch carefully).
-
9
If skipping the cheese, broil frittata until the top is lightly browned, 1 to 3 minutes (making sure it doesn't burn).
-
10
If using a nonstick skillet, slide the frittata onto a serving plate. If using a cast-iron skillet, cut and serve wedges directly from the skillet.