Boil

To boil is to cook food in liquid heated until it bubbles hard, which for water is 100°C (212°F) at sea level. At higher altitudes water boils at a lower temperature, so food takes longer. Boiling is used for pasta, potatoes, eggs, rice, grains and some vegetables. Most other foods, including meat and stews, cook better at a gentler simmer.

How to do it

1. Use a pot large enough that the food is fully covered with room to spare.
2. Cover the pot with a lid to bring it to a boil faster.
3. Salt the water if the recipe says so. For pasta, about 10 g per liter (2 teaspoons per quart) is common.
4. Add the food once the water is at a rolling boil. Potatoes and eggs are the exception: start them in cold water so they heat evenly.
5. Stir in the first minute so pasta and grains do not stick.
6. Adjust the heat to keep the boil steady but not frothing over.

How to tell it is done

The water has big bubbles that keep breaking the surface, even when stirred. For the food: pasta is al dente, potatoes are tender when pierced with a knife, and eggs are timed from when the water comes to a boil.

Why it works

Water cannot get hotter than its boiling point in an open pot, so boiling gives a steady, known temperature. The moving bubbles keep the water circulating, which spreads heat evenly around small pieces such as pasta.

Common mistakes

• Boiling meat hard. The proteins tighten and the meat turns tough and dry. Simmer it.
• A pot that is too small. The water stops boiling when the food goes in.
• Adding oil to pasta water. It does not stop sticking. Stirring does.
• Starting potatoes in boiling water. The outside falls apart before the middle is cooked.
• Leaving the lid on with starchy food. It foams over. Tilt the lid or take it off.

In recipes

"Bring to a boil, then reduce to a simmer" is the most common instruction for soups, sauces and stews. "Boil until reduced" means boil uncovered so water evaporates.