1. Preheat the oven to 400 degrees Fahrenheit.
2. In a large skillet, heat three tablespoons oil over medium heat. Add leeks, half teaspoon salt, and 1/4 teaspoon black pepper and brown for 12 minutes, until lightly golden. Add balsamic vinegar, red wine, pomegranate juice and honey and bring to a boil and cook until syrupy and thickened, about 12 minutes. Remove from heat.
3. In a separate cast iron skillet, heat remaining two tablespoons oil. Sprinkle cod with onion powder, paprika, remaining one teaspoon salt and half teaspoon black pepper. Sear cod, top side down, for three minutes, until slightly browned. Gently flip fish over, add half of leek mixture to skillet, and place in the oven to finish cooking, about six to eight minutes.
4. To serve, transfer fish and onion mixture onto a platter. Top with remaining leek mixture and sprinkle with pomegranate seeds.
5. Alternatively, cod can be cooked in a 400-degree-Fahrenheit oven for 12 to 14 minutes. Make the balsamic pomegranate jam as instructed and serve over fish with a sprinkle of pomegranate seeds.
