Prep time: 20 minutes, including cooling time
Cook time: 11 minutes
Toss this vinaigrette with baby spinach, prosciutto and toasted walnuts for a satisfying first course.
Make ahead: The dressing can be made up to a day in advance. Bring it to room temperature before using. You might need to mix in a tablespoon of oil or water, your choice, to loosen it up.
3 tablespoons olive oil
1 small onion, finely diced (3/4 cup)
1 large tart apple, such as Granny Smith, peeled, cored and cut into 1/4-inch dice
1 tablespoon maple syrup, or more to taste
Freshly ground black pepper
3 tablespoons apple cider vinegar
Heat the oil in a large nonstick sauté pan over medium-high heat.
Add the onion; reduce the heat to medium and cook for 3 to 4 minutes, until the onion just starts to soften, then stir in the apple. Cook, stirring every minute or so, for 5 to 7 minutes, until the apple softens. It's OK if the onion browns a bit. Remove from the heat and transfer to a small bowl.
Mix in the maple syrup, then season with salt and pepper to taste. Let cool for 15 minutes, then stir in the vinegar. Taste, and adjust the seasoning as needed.