Ingredients

• 1 small red onion, thinly sliced
• 1 tablespoon plus 1 teaspoon Dijon mustard
• 2 teaspoons finely grated fresh orange zest
• 4 1/2 tablespoons fresh orange juice
• 1/3 cup olive oil
• 2 heads radicchio (3/4 pound total), cored and coarsely chopped
• 1/2 small head red cabbage, cored and coarsely chopped
• 2 pints cherry tomatoes, halved
• 1/2 teaspoon sugar, or to taste

Instructions

1. Soak onion in cold water to cover 15 minutes.
2. Whisk together mustard, zest, juice, and salt and pepper to taste. Add oil in a slow stream, whisking until emulsified.
3. Drain onion well and toss together with radicchio, cabbage, tomatoes, and enough dressing to coat. Toss salad with sugar and salt and pepper to taste.