Soak 1/2 thinly sliced red onion in ice water for 10 minutes; drain and pat dry. Whisk 2 tablespoons white wine vinegar and 2 teaspoons each honey and Dijon mustard in a large bowl; whisk in 1/4 cup olive oil. Add the onion, 6 peaches (cut into wedges), 1/2 cup chopped candied walnuts and 1/4 cup each fresh basil and mint. Season with salt and pepper and toss.
Photograph by Bobbi Lin