Chop — to cut into pieces. The pieces don’t have to be the same size;
slice — to cut into very thin pieces. You often slice cheese and bread, but you can also slice meat;
grate — when you take something solid and turn it into tiny pieces. You need to use a metal tool for this, called a grater;
peel — to remove the outer layer from food;
boil — to heat up water until it reaches 100 °C or 212°F;
fry — to heat something on the stove using oil or butter;
simmer — to cook something slowly on a very low heat;
roast — to cook meat slowly over a fire or in the oven;
bake — to cook something in the oven, such as bread, cookies or a cake;
mix — to combine two or more ingredients;
marinade — when you put meat or fish in a special sauce with lemon, oil or spices before cooking it;
stir — when you use a spoon to mix something slowly;
dress — when you prepare food for eating by adding salt, pepper, herbs, some sauce, etc.
(For example, when you put olive oil and vinegar on a salad.);
serve — when you put food on the plate.
Other useful words related to cooking:
Dressing (or salad dressing) — a mixture of liquids that is added to a salad to make it tastier. It can include ingredients such as olive oil, vinegar, salt, and pepper;
tasty, appetizing or mouth-watering — synonyms for delicious;
savory — foods are divided into two categories. Desserts are sweet, and foods that aren’t sweet are called "savory.";
raw — food that isn’t cooked, such as sushi or uncooked carrots;
well-done — when meat has been cooked a lot. It’s not red on the inside, but brown;
burned — when something has been cooked too much. When food is burned, it becomes unhealthy. (You can recognize it by its brown or black color.);
peckish — when you are a little bit hungry;
starving — when you are extremely hungry.