Step #4 Add flour mixture to yeast mixture, stirring to mix.
Step #5 Turn dough out onto a floured surface.
Step #6 Knead until smooth & elastic (about 5 mins); add enough of remaining 1/3 c flour, 1 tbsp at a time, to prevent dough from sticking to hands (dough will feel sticky).
Step #7 Place dough In a large-ish bowl coated with cooking spray, turning to coat top.
Step #8 Cover up & let rise in a warm place (85°), free from drafts, 1 1/2 hrs or until doubled in size.
Step #9 (Gently press two fingers into dough.
Step #10 If indentation remains, dough has risen enough.
Step #11 ) Press dough out onto a jelly-roll pan coated with cooking spray.
Step #12 Cover up & let rise for 30 mins.
Step #13 Preheat grill.
Step #14 Combine remaining 2 tbsps oil & balsamic vinegar in a small bowl.
Step #15 Brush oil mixture evenly over zucchini, bell pepper, & onion.
Step #16 Sprinkle top with remaining 1/2 tsp salt & black pepper.
Step #17 Place vegetables on a grill rack coated with cooking spray.
Step #18 Grill zucchini 4 mins on each side or until cooked through.
Step #19 Grill bell peppers & onions 6 mins on each side or until tender.
Step #20 Remove vegetables from grill.
Step #21 Cool completely.
Step #22 Cut bell peppers into 1/4-inch-thick strips.
Step #23 Preheat oven to 425°.
Step #24 Arrange vegetables evenly over surface of dough, & sprinkle with cheese.
Step #25 Bake at 425° for 27 mins or until golden.
Step #26 Sprinkle top with basil.
Step #27 Transfer to a wire rack; cool 10 mins before serving.