Start by preparing all the ingredients. In a skillet with a little olive oil, sauté the chopped garlic until it starts to turn golden. Add the onion, season with salt and pepper, and cook until softened.

When the onion is translucent, add the cod. Stir, pour in a little white wine, and cook until the liquid evaporates and reduces. Sprinkle with chopped parsley.

Add the flour and stir to cook it for a minute. Gradually add the milk, letting the mixture absorb it as you go, until you have a smooth but manageable dough. Sprinkle with nutmeg and adjust the salt. When the dough pulls away from the sides of the pan, it's ready. Transfer to a plate, cover with plastic wrap, and let it rest for at least two hours before shaping the croquettes.

When ready to make the croquettes, beat the egg in one bowl and place breadcrumbs in another. Shape the dough into balls, dip them in egg, then coat with breadcrumbs. Set aside.

Prepare the potatoes for serving. Season with salt, pepper, and your favorite spices, drizzle with olive oil, and bake in the oven at 350°F (180°C), top and bottom heat, for about 35 minutes or until tender when pierced. The peppers should be roasted ahead of time; it's always handy to have them ready.

Heat a saucepan with plenty of oil. When hot, fry the croquettes in batches, being careful not to overcrowd the pan. As they turn golden, remove them and place on paper towels to drain excess oil.

Once all the croquettes are ready, serve them on plates with the roasted potatoes and peppers. They're also delicious with a little aioli. Enjoy!