End of Summer Panzanella

1/2 cup olive oil, plus more for drizzling

1/4 cup white balsamic vinegar

2 small cloves garlic, minced

1/2 teaspoon dried oregano

Kosher salt and freshly ground black pepper

1 pint multicolored cherry tomatoes, halved (about 10 ounces)

1 medium zucchini (about 8 ounces)

1 medium yellow summer squash (about 8 ounces)

2 ears of corn, shucked

1/2 small red onion, sliced into 1/4-inch-thick rounds

One 12-ounce loaf sourdough bread, cut into 1-inch-thick slices

1 cup fresh basil leaves, torn

1/2 cup crumbled ricotta salata or feta

1. Preheat a grill pan or outdoor grill to medium-high heat.
2. Whisk 1/4 cup of the olive oil, the vinegar, garlic, oregano, 1/2 teaspoon salt and several grinds of pepper in a large bowl until smooth and combined. Toss in the tomatoes, then set aside to marinate. 
3. Trim the ends off the zucchini and yellow squash, then cut each lengthwise into quarters. Drizzle the zucchini, corn and onion with 2 tablespoons of the olive oil, 1/2 teaspoon of salt and several grinds of pepper. Brush the bread with the remaining 2 tablespoons of olive oil and season with a pinch of salt.  
4. Grill the zucchini, corn and onion until crisp-tender and charred in spots, 3 to 4 minutes per side for the zucchini and onion, and 6 to 8 minutes for the corn. Grill the bread until toasted and charred, about 2 minutes per side.
5. Slice the zucchini on the bias into 1-inch thick pieces, roughly chop the onion and cut the corn kernels off the cob. Cut the bread into 1-inch pieces. Transfer all to the same large bowl with the tomatoes. Add the torn basil leaves, then toss until the salad is well dressed and combined. Season with more salt and pepper. Transfer to a serving bowl or platter, drizzle with more olive oil and top with ricotta salata or feta if using.