Sauteed Okra and Tomatoes

INGREDIENTS

• 1 tablespoon whole mustard seeds
• 1/2 teaspoon whole cumin seeds
• 1/2 teaspoon ground coriander
• 2 tablespoons extra-virgin olive oil
• 1 small red onion, cut into 1/2-inch-thick wedges
• 1 pound fresh okra, stems and ends trimmed
• 3 medium tomatoes, seeded and cut into 1/2-inch-thick wedges
• Coarse salt and freshly ground pepper