Ultimate roast potatoes

Peel the potatoes, keeping them whole and roughly equal in size (about 8cm).

Parboil in a large pan of boiling salted water for 15 minutes so the insides become fluffy.

Drain in a colander and leave to steam dry for 2 minutes. Give the colander a few light shakes to rough up the edges of the potatoes.

Put the dripping, butter and 1 tablespoon of oil in your largest roasting tray on medium heat. Tip in the potatoes, add a good pinch of sea salt and black pepper, then toss to coat. Spread them out in one fairly snug even layer leaving a small gap between them. Cover and leave in the fridge overnight.

On the day, preheat the oven to 180°C/350°F/gas 4. Take the potatoes out of the fridge and roast for 1 hour, or until crisp and golden all over.

Remove the tray from the oven. Squash the bulb of garlic, lightly crush each unpeeled clove and add to the tray. Pick the rosemary leaves and toss with a little oil. Sprinkle the rosemary over the potatoes and press down on the potatoes with a fish slice.

Roast for a further 20 to 25 minutes, or until golden and crisp.