A tomatillo is a small, green, spherical fruit that looks like a small tomato. In fact, tomatillo means “little tomato” in Spanish. The tomatillo plant, which is a relatively disease-resistant member of the nightshade family, originated in Mexico. Tomatillos can be eaten raw or cooked. They’re perhaps most often associated with salsa verde.
Contrary to its name, a tomatillo is not a little green tomato. Though the two plants are distantly related, they are not the same thing — substitution is not recommended. One of the main differences? Unlike tomatoes, tomatillos are covered in a papery husk that must be peeled away before use. They also have different flavors and textures (tomatillos remain firm when ripe, while tomatoes soften a bit).
Tomatillos are sweet, tart, subtly fruity and a bit earthy. When raw, they’re quite acidic. Cooked tomatillos are a bit milder in flavor. You’ll know it’s time to harvest when the fruit is green and fully fills out the husk. If they’re left to ripen further, tomatillos will split the husk and turn yellow or purple. They’re ready to eat when the husks start to slightly split open at the bottom.