differences in conductivity between the egg yolks and the
egg whites don’t have as strong an effect on their cooking
rates—they basically cook in the same time. Additionally,
the egg whites were pure white, with no crisping or
browning at all on the bottom surface. Some folks like
their egg whites this way. I think those people secretly just
want poached eggs.- Over medium heat, there was still a good amount of
liquid yolk at the top of the egg, while the bottom half of
the yolk became quite firm. The whites took on a touch of
browning (even more if I used butter instead of oil—the
milk proteins in the butter brown and stick to the eggs).
This is a good compromise for folks who like some liquid
yolk but don’t want their whites to show any transparency
at all. - Over high heat, you can get whites that are completely
set with yolks that are still almost completely liquid, but
you run into another problem: the bottom of the eggs
burns long before the rest of the egg is ready to eat.
For the simplest fried eggs, moderate heat is the way to
go. Whether you’re using butter or oil makes little difference
in the cooking, as long as you make sure that the milk
proteins in your butter don’t burn before you slip the eggs
into the pan; it’s best to add them just after the foaming
subsides. (This is an indication that the water in the butter
has completely evaporated and the pan is somewhere in the
250°F range). Butter will give you richer flavor and deeper
browning, while oil will give you cleaner egg flavor and
slightly crisper bottoms—it’s all down to personal