Grilled Cod with Spinach and Tomatoes

Ingredients (10)

• + 1 (4 ounce) fillet cod add to pantry
• + salt and ground black pepper to taste add to pantry
• + salt and ground black pepper to taste add to pantry
• + 1 pinch garlic powder, or to taste add to pantry
• + ¼ cup roughly chopped spinach, or to taste add to pantry
• + ¼ tomato, seeded and diced add to pantry
• + 1 tablespoon chopped onion add to pantry
• + 1 tablespoon olive oil, or to taste add to pantry
• + 1 tablespoon balsamic vinegar, or to taste add to pantry
• ✓ 1 slice mozzarella cheese, cut into cubes