Grilled Pizza with Hot Sausage, Grilled Peppers and Onions and Oregano Ricotta

• 1/2 pound Italian hot sausage
• 1 large red onion, cut into 1/4-inch thick slices
• 2 large yellow pepper, cored, seeded and quartered
• 2 large red pepper, cored, seeded and quartered
• Olive oil
• Salt and pepper
• 1 recipe favorite pizza dough, rolled into 4 (6-inch) rounds
• 1/2 pound grated fontina cheese
• 1 cup sheep's milk ricotta
• 2 tablespoons extra-virgin olive oil
• 2 tablespoons chopped fresh oregano
• Basil Vinaigrette, recipe follows

Basil Vinaigrette:

• 1/2 cup fresh basil leaves
• 1/4 cup white wine vinegar
• 1 tablespoon honey
• Salt and freshly ground black pepper
• 1/2 cup olive oil