Tuscan kale with caramelized onions and red wine vinegar

Tuscan kale, also known as cavolo nero, dinosaur kale, and lacinato kale, is sweeter and more tender than regular kale, which can be used instead but may require more cooking time.

1 tablespoon extra-virgin olive oil

1 large red onion, halved and thinly sliced into half-moons

1 large garlic clove, thinly sliced

3 / 4 teaspoon coarse salt

2 tablespoons red-wine vinegar

1 pound Tuscan kale, middle stems removed, leaves cut into 1 1 / 2 -inch pieces

• Combine the oil, onion, garlic, and 1 / 4 teaspoon salt in a large saute pan; cook over medium heat, stirring occasionally, until the onion is lightly browned, about 5 minutes. Reduce heat to mediumlow; cook until the onion is soft, about 10 minutes.
• Add the vinegar to the pan, and raise heat to medium-high. Add the kale, 1 / 4 cup water, and remaining 1/ 2 teaspoon salt; cook, stirring, until the kale begins to soften, about 3 minutes. As the pan becomes dry, add another 1 / 4 cup water, and cook until the kale is tender, about 3 minutes more. Serve immediately.
• SERVES 4