In addition to how pretty they are, the other thing I like about this method of cooking eggs is how close to foolproof it is. Here's how:
1. If you don't have a 9- or 10-inch non-stick skillet, go out and get one. You wouldn't attempt to make cupcakes without a cupcake tin, would you? Exactly.
2. Get good eggs. As good as the toppings are, eggs are undoubtedly the star of this dish, and your frittata will only be as good as your eggs are. So buy the best, freshest eggs you can find, ideally at a farmers market. I like to use Chino Valley Ranchers' eggs with a bright yellow yolk because they taste great and the color reminds me of eggs I buy in Italy.
3. Have all your topping ingredients prepared, measured out and ready because once you start cooking the eggs, everything happens very fast. And the only thing that can go wrong is that you overcook the eggs, and the only way that can happen is if you have to scramble around (no pun intended) getting your ingredients at the moment you're supposed to be scattering them over the eggs.
4. Bring your toppings to room temperature or warm them before making your frittata. They aren't on the eggs long enough to warm through, and biting through cold, refrigerated garlic confit will damp even the best frittata experience.
5. If you're inventing your own toppings, make sure that the ingredients are delicate; cheese needs to either be finely grated, or a soft crumbling cheese such as goat cheese or ricotta. Something like a cheddar won't melt the way it would in a traditional frittata or omelet, so I wouldn't recommend it. Ingredients such as bacon or roasted peppers need to be chopped very fine. These soft-cooked eggs are too delicate to have big, weighty hunks of anything on top.
6. When whisking the eggs, I add water because I think it helps to emulsify the eggs and whites. Also, make sure to season them properly as called for in the recipes. You need to add enough salt to the raw eggs as it will be impossible to properly season the eggs once they're cooked.
7. When cooking the eggs, use medium-low to low heat. Think of scrambled eggs as a custard: You want them light and tender, with no color (browning) on them whatsoever. The way to do this is to control the heat, and if they seem to be cooking too quickly, lower it. (You almost can't cook them too low.)
8. As the eggs begin to cook, draw the cooked egg toward the center of the pan and tilt the pan so the raw egg runs onto the surface of the skillet. While you do this, try to keep the pan on the heating surface as much as possible rather than holding the skillet above the heat.
9. These frittatas are best cooked for a small group, and by small, I mean one or two people, as they need to be cooked one at a time. I guess if you have two 9-inch skillets and you are well coordinated, you could do two at a time, like a line cook. In any case, you'll serve them one at a time, sliding each individual frittata onto a plate and handing it to some lucky eater, as it is done.