1 medium
red onion,
very thinly sliced — preferably with a mandoline 2/3 cup
red wine vinegar (or more if needed to cover the onion) 1 teaspoon sugar or agave Pinch salt 1 can chickpeas, drained and rinsed 2/3 cup chopped sun - dried tomatoes (oil - packed or other ready - to - use, see note above) 1 small head radicchio (Treviso is
nice here) cored and diced (about 1 1/2 cups) 2 tablespoons capers, rinsed 3 - 4 tablespoons chopped fresh basil 1/4 teaspoon salt, or more to taste Freshly ground black pepper 1 lb.