Grilled Vegetable Salad with Lemon-Mustard Vinaigrette

Preparation

1. For vinaigrette:

   Step 1

   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.

2. For vegetables:

   Step 2

   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.

   Step 3

   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.

   Step 4

   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.