Right now I can cook from recipes. That’s not quite the cook I wish I were. Some cooks don’t need recipes. They look at the fridge, at the pantry, and thirty minutes later there is something great at the table. How do they do it? Practice, they tell me. Necessary but not sufficient, I discover. Encyclopedic knowledge is needed in cooking. Should I boil or fry asparagus? How many saffron twigs for two cups of rice?…