Poach the desalted cod in simmering water with a bay leaf for 10 minutes. Drain and flake the fish.
Mash your boiled potatoes until smooth (or use a food mill).
In a pan, gently sauté garlic in olive oil (don’t brown it!).
Combine cod, potatoes, garlic oil, and milk. Stir or blend with a hand mixer until creamy. Season with pepper and nutmeg.
Can be served over or even you can bake as said below for extra flavor and shelf life.
Transfer to a baking dish, top with a little olive oil or grated cheese (optional), and bake at 180°C (350°F) for 15–20 minutes until golden.
Garnish and serve hot with crusty bread or salad!