Step 1

Heat the oven to 200C/fan 180C/gas 6. Prick the potatoes all over with a fork and sprinkle with a little sea salt. Bake until tender, approx 1 hour.

Step 2

Halve the potatoes and scoop out the flesh leaving a 1/2 cm layer. Mash with 2 large knobs of butter and the milk then season. Mix in the egg, then 3/4 of the cheese, mustard and a few good dashes of Worcestershire sauce.

Step 3

Pile the mix back in the shells then sprinkle over the rest of the cheese and put back in the oven for 15-20 minutes until golden. Serve with salad leaves.