In the United States the orange-flesh sweet potato (yam) is available year-round but peaks in the winter. When purchasing, look for small to medium sweet potatoes that have smooth skin and are firm and free of soft spots. Store whole unpeeled sweet potatoes in a cool, dry place for up to 1 week (do not refrigerate or they will dry out).
Tip: One pound of sweet potatoes is about 2 medium sweet potatoes or 2 3/4 cups cubed.
Before boiling sweet potatoes, scrub with a clean produce brush and rinse with cool water. Use a vegetable peeler or paring knife to peel sweet potatoes. Using a knife, cut off any woody portions and ends. Cut into bite-size cubes.
Tip: Cut sweet potato cubes as close to the same size as you can for even cooking.
Select a saucepan or Dutch oven that will be large enough to hold the sweet potatoes without crowding them. Fill the pot about halfway (you will need just enough water to cover the sweet potatoes) and add a dash of salt. Bring to boiling. Add sweet potatoes.
How long to boil sweet potatoes: For one pound of sweet potatoes, cover the pan and cook sweet potatoes in the boiling salted water for 10 to 12 minutes or until just tender on the outside but resistant in the center when pierced with a knife. For soft, tender sweet potatoes, cook for 20 to 30 minutes.
Place a colander in the sink. Remove the lid from the pan and carefully pour the sweet potatoes into the colander. Drain off the water. Set sweet potatoes aside until cool enough to handle, or run cold water over them to quick-cool. For an easy side dish, toss cooked sweet potato cubes with butter, salt, and pepper, and serve. Or use the cooked cubes in salads, tacos, soups and stews, and casseroles. You can also mash the cubes to make mashed sweet potatoes or to use as an ingredient in cakes, breads, pies, and savory dishes.