Clean the cod filets and pat them dry with paper towels—season with salt and pepper.
Heat a non-stick skillet to medium and add the olive oil.
Place the filet's skin side down and let them cook for about 5 minutes on each side; reserve.
In the same oil (or adding a bit more if needed), add the garlic, onion, and pepper. Cook for a few minutes, just until the onion is translucent.
Add the potatoes and fish stock and bring to a boil. Lower the heat and let them simmer, covered, until the potatoes are soft (around 15 minutes).
In another skillet, heat the olive oil and add the sweet paprika. Cook for a couple of minutes and reserve.
Once the potatoes are soft, add the cod back to the skillet and top with the oil with paprika.
Serve with fresh parsley.