Classic three-bean salad uses green beans, yellow or wax beans and kidney beans. Other ingredients are onions, garlic, oil, cider vinegar, salt, parsley and sugar. Making it is just a matter of cooking the beans, making the dressing and marinating the bean mixture in the dressing.
The three-bean salad recipe on FoodNetwork.com calls for 8 ounces each of fresh green beans and wax beans. Trim their ends and cut in half crosswise. Add some salt to a pot of water and bring it to a boil. Fill a large bowl with ice water and set aside. Cook the green beans and wax beans in the boiling water for four or five minutes until they are crisp-tender, then drain the beans. Put them in the bowl of ice water to stop further cooking and set their color, then drain out the ice water.
Mince half of a small red onion, soak it in water for five minutes and drain. Combine it with the cooked beans in a medium bowl. Drain and rinse the 15 ounces of kidney beans, and mix them into the bowl.
For the dressing, combine 1/4 cup of sugar, 1/3 cup of cider vinegar, 1/4 cup of vegetable oil and 1/2 teaspoon of kosher salt in a small saucepan and bring to a simmer. Pour it over the bean mix and let it marinate for an hour at room temperature, tossing it several times. Season with salt and pepper to taste and add a tablespoon of minced flat-leaf parsley before serving.
Food.com's recipe uses red wine vinegar instead of cider vinegar, canola oil instead of vegetable oil and includes two cloves of minced garlic. Instructions advise letting the salad sit overnight in the refrigerator to blend the flavors and bringing it to room temperature 30 minutes before serving.