- 2 cups shelled fresh butter beans (1 1/2 pounds unshelled), frozen (thawed) butter beans or baby lima beans
- 4 tablespoons canola oil, divided
- 2 cups corn kernels, fresh (from about 4 large ears; see Tip) or frozen (thawed)
- 1 Vidalia or other sweet onion, finely chopped
- 1 small yellow squash, chopped
- 1 small zucchini, chopped
- 1 clove garlic, minced
- 2 medium tomatoes, seeded and chopped
- 1/2 stalk celery, very finely chopped
- 1/2 cup very thinly sliced fresh basil
- 2 tablespoons cider vinegar
- 1 teaspoon Dijon mustard
- 1 teaspoon salt
- Freshly ground pepper to taste
- Place beans in a medium saucepan and cover with water. Bring to a boil. Reduce to a simmer and cook until tender, about 30 minutes for fresh beans, about 25 minutes for frozen. Drain well. Transfer to a large bowl.
- Meanwhile, heat 1 tablespoon oil in a large skillet over medium heat. Add corn, onion, squash and zucchini and cook, stirring, until crisp-tender, 4 to 5 minutes. Add garlic and cook, stirring, until fragrant, 45 seconds to 1 minute. Add the cooked vegetables to the bowl of beans. Transfer to the refrigerator to cool for at least 1 hour.
- When the beans and vegetables are cool, stir in tomatoes, celery and basil.
- Whisk vinegar and mustard in a bowl. Add the remaining 3 tablespoons oil in a slow, steady stream, whisking constantly, until the dressing is creamy and well combined. Season with salt and pepper. Drizzle the dressing over the succotash and toss to coat.