Boiling, sautéing, grilling, baking — which one is preferred when? Once you grasp the logic of these four basic methods, you'll start to understand for yourself why recipes say "do it this way."
Boiling
Cooking in water, at the 100 °C limit. The method for vegetables, legumes, eggs, and pasta; flavor passes into the water, which is why the boiling water is often put to use afterward. It's gentle and forgiving — the technique of dishes that aren't in a hurry.
Sautéing
Short cooking in a little oil, over high heat, with constant movement. It requires small, evenly cut ingredients; if you put more into the pan than it can hold, the ingredients release their water and boil instead of browning.
Grilling
Direct contact with high heat: a caramelized crust outside, a juicy texture inside. Pat meat and vegetables dry before putting them on the grill — surface moisture is spent on evaporating instead of browning, and that signature char-marked seal never forms.
Baking
Even cooking from every side with enclosed hot air. Watch the color and texture, not the clock: the same recipe reaches doneness in a different time depending on your oven's actual temperature and the material of the pan. Every time you open the oven door, the temperature drops and the time stretches out.