Creating this amazing dish is a straightforward process if you follow these simple steps:

1. Preheat the Oven: Preheat your oven to 400°F (200°C) for roasting the tomatoes.
2. Prepare the Tomatoes: In a bowl, toss the cherry tomatoes with 2 tablespoons of olive oil, balsamic vinegar, salt, and pepper. Spread them out evenly on a baking tray.
3. Roast the Tomatoes: Roast the tomatoes in the preheated oven for about 15-20 minutes, or until they are soft and slightly caramelized.
4. Prepare the Cod: While the tomatoes roast, season the cod fillets with garlic powder, onion powder, salt, and pepper.
5. Grill the Cod: In a grill pan or outdoor grill, heat the remaining 2 tablespoons of olive oil over medium-high heat. Place the seasoned cod fillets on the grill and cook for about 4-5 minutes on each side, or until the fish flakes easily with a fork.
6. Make the Creamy Dill Sauce: In a small bowl, mix together sour cream, chopped dill, lemon juice, and a pinch of salt. Adjust seasoning as needed.
7. Plate the Dish: Once the cod and tomatoes are cooked, place the grilled cod on a plate, top with the roasted tomatoes, and drizzle the creamy dill sauce over the top.
8. Serve Immediately: Garnish with additional dill if desired and serve with lemon wedges.

These straightforward steps will guide you in preparing this incredible dish with ease, allowing your culinary skills to shine through!