675g/1lb 5oz cooked turkey and ham, cut into 2cm chunks
For the mashed potato
knob of lactose free butter
1 free-range egg yolk
3 tbsp lactose free milk
salt and freshly ground black pepper
Preheat the oven to 180C/360F/Gas 4. In a saucepan large enough to hold all the meat, melt the lactose free butter and add the chopped celery. Season with salt and freshly ground black pepper and cook, without browning, on a gentle heat for 8-10 minutes, until the celery is completely soft.
Add the lactose free cream and stock and bring up to the boil and simmer for a few minutes to thicken. Meanwhile, in a separate frying pan, heat the zucchini with a knob of lactose free butter (you might need to do this in two batches) for 3-4 minutes, or until soft.
Add tarragon or majoram to the zucchini and season to taste with salt and freshly ground black pepper. Add the meat and the zucchini and stir well.
Meanwhile for the mashed potato, place the potatoes in a saucepan of boiling water and cook until soft. Drain the potatoes and return them to the saucepan. Mash roughly and then add the lactose free butter, egg yolk and lactose free milk and mash to a thick paste. Season, to taste, with salt and freshly ground black pepper.
Pour the lactose free cream, zucchini and meat mixture into a shallow gratin dish and top with the mashed potato. Place in the oven for about 20-30 minutes until the potato topping is golden brown and the filling is hot.