Pat the fish chunks dry with paper towels and season them lightly with a pinch of salt and pepper. Set aside in the refrigerator while you prepare the vegetable base.

In a large Dutch oven or heavy-bottomed pot, drizzle 2 tablespoons of olive oil over the bottom. Create an even layer using half of the sliced onions, garlic, and bell peppers, followed by an even layer of half the sliced potatoes.

Repeat the layering process with the remaining onions, garlic, bell peppers, and potatoes. Pour the diced tomatoes with their juices, white wine, and the remaining 2 tablespoons of olive oil over the top of the vegetables.

Sprinkle the smoked paprika, bay leaf, salt, and black pepper over the pot. Cover with a tight-fitting lid and bring to a gentle boil over medium heat. Once boiling, reduce the heat to medium-low and simmer undisturbed for 20 to 25 minutes, or until the potatoes are fork-tender.

Carefully arrange the seasoned fish chunks on top of the cooked vegetables and sprinkle with half of the fresh cilantro. Cover the pot again and simmer for another 8 to 10 minutes, or until the fish is completely opaque and flakes easily with a fork. Do not stir, as this will break up the delicate fish.

Remove the pot from the heat and discard the bay leaf. Ladle the stew into warm, shallow bowls, garnish with the remaining fresh cilantro, and serve immediately with toasted crusty bread to soak up the flavorful broth.