The key to keeping eggs from sticking to cast iron is preheating the pan to the right temperature. Here is how to do it based on your pan's finish:

Pan with a smooth finish, for geeks:
Heat your cast iron skillet over high heat until it reaches a temperature of
395 °F (200 °C). It takes approximately 4 minutes to heat the pan from cold to this temperature.

Pan with a polished finish, for the most demanding:
Heat your cast iron skillet over high heat until it reaches a temperature of
340 °F (170 °C). It takes approximately 3 minutes to reach this temperature starting from a cold pan.

Don't have a thermometer? Do it the old-fashioned way:
Drop a few drops of water into the hot cast iron skillet. If the drops dance and bounce upon touching the surface, the temperature is just right. If they evaporate quickly, the pan is too hot. If nothing happens, wait for it to heat up more and try again.

To prevent eggs from sticking to cast iron, coat the pan with oil or butter. We recommend two methods:

Butter: Add a good-sized knob of butter and use a heat-resistant spatula to spread it as it melts. Move the pan back and forth to ensure the entire cooking surface is coated with butter. Do not let the butter burn. We may be butter fanatics, but we believe this yields the tastiest result.

Oil: Apply a thin layer of cooking oil to the cooking surface using a lint-free paper towel (this prevents oil buildup).

No matter how much of an expert you think you are at cracking eggs, please, do not crack them on the edge of a cast iron skillet. Sooner or later, one day you will be distracted and hungry, and the egg will spill inside and outside of the pan. It is nothing that cannot be fixed, but it is no way to start the day.

We suggest that you crack the egg first into a shallow dish, a cup, or a container. To master the art of the sunny-side up egg, add the whites to the pan first, and then the yolk on top. This will prevent the yolk from coming into direct contact with the pan, since, due to its composition, it tends to stick more easily.

Place the egg in the center of the skillet and make sure it is on a burner of an appropriate size. Cover the skillet, making sure it is tightly sealed.

Turn the heat down to the lowest setting. Do not worry, cast iron retains heat well. Cook the egg for 2 minutes so that it is well done, adjusting the time according to your desired level of doneness for the yolk.

1. Ensure that the pan is level before you begin.
2. Let the eggs reach room temperature before cooking them, as cold foods tend to stick to hot surfaces.
3. Crack the eggs on a flat, hard surface to prevent the shell from splintering or pieces from falling into the egg.
4. Avoid moving the eggs once they are in the pan. Move them only when a crust forms and the egg begins to pull away from the surface.