Grilled Veggie-Portobello Mushroom Burgers

Ingredients (7)

• + 6 large portobello mushroom, stems removed add to pantry
• + 1 eggplant, sliced into 1/2 inch rounds add to pantry
• + 1 medium yellow squash, cut into 1/4-inch slices add to pantry
• + 1 zucchini, cut into 1/4-inch slices add to pantry
• + 1 (16 fl oz) bottle balsamic vinaigrette add to pantry
• ✓ 1 (4 ounce) package crumbled blue cheese
• + 6 hamburger buns, split and lightly toasted add to pantry