In the Thai manner, the vegetables are rolled up in lettuce leaves and dunked in the sauce.
Prepare grill or broiler.
Combine first 4 ingredients in a large zip-top plastic bag, and seal. Marinate 15 minutes, turning occasionally. Remove mushrooms from bag; discard marinade. Place mushrooms on a grill rack or broiler pan coated with cooking spray; cook 3 minutes on each side. Cut mushrooms into 1/2-inch-thick slices; set aside.
Steam green beans, covered, 5 minutes or until tender.
Arrange romaine and radicchio leaves on a large platter. Divide mushrooms, green beans, bell pepper, and corn evenly over lettuce. Sprinkle with basil. Roll up, and serve with Spicy Thai Dipping Sauce.