Place peeled and chunked potatoes in a large pot and cover with cold water by 2 cm. Add 1/2 tsp salt. Bring to a boil over high heat, then reduce to a simmer and cook until potatoes are tender when pierced with a fork, about 15–20 minutes depending on size.

Drain and dry

Drain potatoes thoroughly in a colander. Return them to the hot pot off the heat for 1–2 minutes to evaporate excess moisture — this prevents watery mash.

Mash and season

Mash potatoes until smooth (use a potato ricer or masher). Add the butter, milk, 1 tsp salt, 1/2 tsp pepper, and nutmeg if using. Mix until creamy but fairly firm — mixture should hold shape; if too wet, add a little more mashed potato or reduce milk. Taste and adjust seasoning.

Filling (Optional Add-ins)

Sauté onion

If using onion, heat 1 tbsp olive oil in a small skillet over medium heat. Add the diced onion and a pinch of salt and sauté until soft and translucent, about 4–5 minutes. Let cool slightly.

Combine add-ins

Fold the cooked onion, chopped ham or shredded chicken, and chopped parsley into the mashed potato base until evenly distributed. Adjust salt and pepper to taste. The finished filling should be cool or at least room temperature before shaping — refrigerate 20–30 minutes if necessary to firm up.

Forming & Coating

Shape croquettes

Line a baking sheet with parchment. With lightly floured hands, portion about 50–60 g of potato mixture (roughly 2–3 tablespoons) and shape into logs (about 7 cm/3 in long) or small ovals. Place on the prepared sheet. Continue until all mixture is used. Chill shaped croquettes in the fridge for 20–30 minutes to help them hold shape.

Prepare dredging station

Set up three shallow bowls or plates: one with the flour seasoned with 1/4 tsp salt and 1/8 tsp pepper, one with the beaten eggs, and one with the breadcrumbs mixed with the remaining 1/4 tsp salt and 1/8 tsp pepper. For extra-crisp coating, use panko breadcrumbs or double-dip (flour -> egg -> breadcrumbs, then egg -> breadcrumbs again).

Coat croquettes

Working in batches, lightly dredge each chilled croquette in flour, shake off excess, dip in beaten egg, then roll evenly in breadcrumbs until fully coated. Place coated croquettes back on the tray and chill 10–15 minutes to set the coating.

Frying & Serving

Heat oil

Pour oil into a heavy-bottomed skillet or deep saucepan to a depth of about 2.5 cm (1 inch) or use a deep-fryer set to 175°C (350°F). Heat the oil over medium-high heat until it reaches 170–180°C (340–355°F) or a small breadcrumb sizzles and browns in about 20–30 seconds. Maintain temperature between 165–180°C to avoid overbrowning.

Fry croquettes

Carefully slide 4–6 croquettes into the hot oil without overcrowding (work in batches). Fry, turning occasionally, until evenly golden brown and crisp, about 2.5–4 minutes per batch depending on size. Remove with a slotted spoon or spider and drain on a wire rack set over a baking sheet or on paper towels.

Finish and serve

If desired, keep cooked croquettes warm in a 90–100°C (200–210°F) oven on a rack while frying remaining batches. Serve hot with lemon wedges and your chosen dipping sauce (aioli, mustard, or similar).