- 3 tablespoons red wine vinegar
- 1 shallot, finely chopped
- 1 garlic clove, minced
- 1 tablespoon chopped fresh Italian parsley
- 1 tablespoon chopped fresh chives
- 1 tablespoon chopped fresh basil
- 1 tablespoon chopped fresh dill
- 1 tablespoon Dijon mustard
- 1 tablespoon fresh lemon juice
- 3/4 cup extra-virgin olive oil
- 20 asparagus spears, each trimmed to 5-inch length
- 8 green onions, green tops trimmed
- 4 medium zucchini, each cut lengthwise into 1/4- to 1/3-inch-thick slices
- 2 large ears of corn, husked
- 4 medium heads of Belgian endive
- 2 small heads of radicchio, halved through core
- 6 plum tomatoes, halved lengthwise
- Olive oil (for brushing)
- Combine first 9 ingredients in medium bowl. Gradually whisk in oil; season with salt and pepper. DO AHEAD Can be made 2 hours ahead. Let stand at room temperature.
- Prepare barbecue (medium-high heat). Arrange all vegetables on baking sheets. Lightly brush all vegetables with oil; sprinkle with salt and pepper. Grill asparagus, green onions, zucchini, and corn until lightly charred and just tender, turning occasionally, about 5 minutes for green onions, 8 minutes for asparagus and zucchini, and 10 minutes for corn. Return vegetables to same sheets.
- Grill endive and radicchio until lightly charred, turning often, about 8 minutes. Transfer to baking sheets with other vegetables. Place tomatoes, skin side down, on grill and cook until just charred, about 3 minutes. Turn tomatoes; grill until just beginning tosoften, about 1 minute longer. Transfer to sheets with other vegetables.
- Cut asparagus, green onions, and zucchini crosswise into 1-inch pieces; place in large bowl. Cut corn kernels from cobs; add to bowl. Cut endive in half lengthwise. Remove cores from endive and radicchio. Chop into 1/2- to 3/4-inch pieces; add to bowl. Coarsely chop tomatoes. Using slotted spoon, add tomatoes to bowl. Do ahead Can be made 2 hours ahead. Let stand at room temperature. Mix vinaigrette into vegetables. Season with salt and pepper.