Step 1

Heat the oven to 200C/180C fan/gas Peel the potatoes and cut them into long chip shapes – the thickness is entirely up to you, though the width of a finger is ideal. Rinse under the cold tap and pat dry with a tea towel.

Step 2

Spread the chips on a large non-stick baking tray and toss with the olive oil and celery salt. Lie them flat in a single layer – use two trays rather than overcrowd one.

Step 3

Roast for 45-50 mins, turning now and then. When cooked they should be golden brown and crisp with a light fluffy centre. Scatter on sea salt to serve.