Roast Potatoes

Name: Roast Potatoes
Prep time: 20 min
Cook time: 1 h
Total time: 1 h 20 min
Cuisine: United Kingdom
Ingredients: 1½ kg (3⅓ lb) floury potatoes (Maris Piper, King Edward, Russet), peeled and cut into 5 cm chunks; 20 g (1 tbsp + ½ tsp) fine sea salt, for the water; ½ tsp baking soda; 90 ml (6 tbsp) duck or goose fat, beef dripping or olive oil; 4 cloves garlic, lightly crushed, skin on; 3 sprigs rosemary; flaky sea salt, to finish

Glass-crisp outside, fluffy inside — parboiled, roughed up and roasted hot

Serves: 4
Hands-on: 20 min
Total: 1 h 20 min
Level: Easy

The best roast potatoes have a craggy, crackling shell and an interior like mashed potato. Three steps get you there: parboil in salted water with a little baking soda, shake them hard in the pan to rough up the surfaces, then roast in a generous layer of very hot fat.

Ingredients

1½ kgfloury potatoes (Maris Piper, King Edward, Russet) (3⅓ lb)peeled and cut into 5 cm chunks
20 gfine sea salt (1 tbsp + ½ tsp)for the water
½ tspbaking soda
90 mlduck or goose fat, beef dripping or olive oil (6 tbsp)
4 clovesgarliclightly crushed, skin on
3 sprigsrosemary
flaky sea saltto finish

Diet: Gluten-free, Dairy-free
Allergens: None of the EU 14
Origin: United Kingdom

Method

Heat the oven to 230°C (450°F). Put the fat in a large heavy roasting pan or sheet pan and slide it in to heat.
Put the potatoes in a large pot with 2 L cold water, the salt and the baking soda. Bring to a boil and simmer until the outsides are soft and a knife meets only slight resistance in the center, 8–10 minutes after boiling. 12 min
Drain well and leave in the colander for 2 minutes to steam off. Return to the pot, cover, and shake hard several times until the edges are fluffy and the potatoes are coated in a starchy paste. 2 min
Carefully take out the pan of fat — it should be shimmering. Tip in the potatoes and turn each one in the fat. Spread them out with space between.
Roast 20 minutes without touching. 20 min
Turn the potatoes over, add the garlic and rosemary, and roast until deep golden, crisp and crackly all over, 25–30 minutes more, turning once more. 28 min
Season with flaky salt and serve immediately.

Why it works

Baking soda makes the water alkaline, which breaks down the potatoes' surface pectin so it turns into a starchy paste when shaken. That paste fries in the hot fat into a thin, glassy, ultra-crisp crust. Floury potatoes have large, loose starch cells that cook up fluffy inside.

Common mistakes

Cold fat: the potatoes stick and absorb grease. The fat must be hot before they go in.
Crowding the pan: they steam. Use two pans if needed.
Too much baking soda: more than ½ tsp turns the potatoes mushy and soapy.

Variations

Lemon and oregano: Swap the rosemary for 1 tsp dried oregano and add the zest of a lemon with the flaky salt.

Make ahead and storage

Parboil and rough up up to 1 day ahead; cool, refrigerate uncovered, and roast from cold (allow 5 minutes extra). Parboiled potatoes also freeze for 1 month and roast from frozen.