2 small zucchini, cut into 1/4-inch-thick rounds |
2 small yellow summer squash, cut into 1/4-inch-thick rounds |
8 ounces mushrooms, quartered |
12 cherry tomatoes, stemmed, halved |
1 tablespoon dijon mustard |
1 tablespoon white wine vinegar |
1/4 cup olive oil |
2 teaspoons minced fresh oregano or 3/4 teaspoon dried, crumbled |
1/2 teaspoon ground cumin |
salt and freshly ground pepper |