Split green peas are dried field peas — varieties are peas that are grown specifically for drying, rather than eating fresh as you would a “garden pea.”After drying, they are split in half — you can get these peas whole as well, but the split ones cook faster.
They are mostly used to make soups, casseroles, or pease pudding. They can also be used in Indian cooking.
Don’t soak split green peas first before cooking with them — there’s no need to soak before cooking.
Wash them in a sieve or in a big bowl of water. The standard advice is to then pick through them to make sure there are no small stones in them, though it can be very difficult to tell at this stage.
You can cook them in water, or in stock. Stock can be useful if you are planning on incorporating the liquid into a soup. Don’t add salt to the water at this cooking stage, but do consider some aromatics like chopped onion or celery, bay leaves, etc.
Cooking time is about 30 minutes in a regular pot; 10 minutes in a pressure cooker.
In a regular pot, for every 250 g (1 cup) of split green peas, use about 750 ml (3 cups) of liquid. The peas will cook in about 30 minutes, and after that turn to mush, so test them as they approach the 30 minute mark and if they need them to stay intact for what you are making, be ready to whistle them out of the water. Of course if you want them dissolved completely for a pea soup, then you may want to leave them in a few more minutes.
In a pressure cooker, for 250 g (1 cup) of dried split peas, use about 750 ml (3 cups) of liquid, or enough so that the peas are covered with about 5 cm (2 inches) of liquid. Add a tablespoon of oil to help prevent foaming. The pot must be no more than 1/2 full. Cook the peas 6 minutes (for firm) to 10 minutes (for mushy) on high pressure (again, no need to soak first), lowering the heat to its lowest setting once pressure has been reached to avoid scorching the peas.
Yellow split peas; Lentils
1 pound (450 g) split peas, uncooked = 2 to 2 1/3 cups * uncooked = 6 cups cooked
1 kg split peas, uncooked = 4 to 4 1/4 cups * uncooked
* Ed: depending on how large the variety of split pea is, and how much moisture was removed in the drying.