BEAT vinegar, juices, mustard and garlic in large bowl with wire whisk until well blended. Gradually add oils, beating constantly. Add salt and black pepper; mix well. Cover. Refrigerate until ready to use.
GARLIC Confit: Pour oil into small saucepan. Add garlic, thyme and crushed red pepper. Bring to boil on medium heat. Reduce heat to medium-low; simmer 4 min. Remove from heat. Let stand 30 min. (Garlic will be soft when pierced with tip of small knife.) Set aside.
COOK pasta as directed on package; drain. Rinse, then drain again. Place in large bowl. Add oil; toss to coat. Cool, then refrigerate while preparing vegetables.
COMBINE mushrooms, fennel, zucchini, asparagus, onions and yellow squash in shallow non-reactive pan. Add 3-1/2 cups of the Vinaigrette (or 1-3/4 cups of the Vinaigrette for trial recipe); toss to coat. Refrigerate 30 to 45 min. to marinate. Meanwhile, whisk mayonnaise into remaining 1 cup Vinaigrette (or into remaining 1/2 cup Vinaigrette for trial recipe). Cover. Refrigerate until ready to use.
DRAIN vegetables; discard marinade. Grill vegetables until crisp-tender. Remove from grill; spread into single layer on full sheet pans. Cool completely. Cut into bite-size pieces.
DRAIN Garlic Confit; discard oil and thyme. Add garlic to Pasta along with the grilled vegetables, mayonnaise mixture, bell peppers, chervil, chives and parsley; toss to coat. Serve at room temperature.