Simmer

Homemade citrus curd—a mixture of eggs, sugar, butter, and orange and lime juices—adds tangy flavor to this mousse.

If you prefer a completely smooth texture, you may pass the potatoes and celery root through a food mill or ricer after they have been cooked.

Frozen lima beans may be substituted for fava beans; start with the second step.

Water or stock can be substituted for any or all of the milk, but milk makes a creamier polenta.

Leeks should be cleaned thoroughly. After slicing, place the pieces in a large bowl of cold water. Let stand about 10 minutes, then remove them with a slotted spoon.

Any combination of kale, chard, and mustard or collard greens works well.

White asparagus spears are generally thicker than their green counterparts, so be sure to trim the tough ends of the stalk and cook until they are perfectly crisp-tender.

Flageolet, pale green kidney beans, are prevalent in French cooking. Their delicate flavor is well suited for simple preparations and is particularly good with lamb.