Wash the nettles, then blanch in boiling water for a couple of minutes. Squeeze out as much water as possible and roughly chop.
Melt the butter in a pan and cook the shallots over a low heat until soft, then add the mushrooms, bacon and nettles and cook until softened. Pour in the sherry, turn up the heat and cook until the liquid has evaporated.
Remove from the heat and stir in the double cream. Season with sea salt and freshly ground black pepper.
Season the veal. Heat the oil in a pan over a high heat, and then sear the fillets on both sides for 2-3 minutes. (Leave the pan to one side, you'll need it later to make the sauce.)
Roll out the puff pastry thinly and cut out 4 squares big enough to envelop the meat. Divide the duxelle mixture between them, leaving enough of a border to seal the pastry. Place a fillet onto each square and brush the edges with the beaten egg. Carefully fold the edges of the pastry to seal the meat inside, then turn over and place on a baking sheet.
Brush the tops with the beaten egg. Roll out the remaining pastry and cut squares using a lattice cutter, then carefully place on to each parcel. Brush again with the egg and sprinkle with poppy seeds.
Rest in the fridge for 30 minutes before cooking. Cook at 200'C for 15 minutes for rare and 20 minutes for medium, then set aside to rest.
To make the fondant potatoes; peel the potatoes, top and tail them and cut into even sized barrel shapes. Heat the butter in a saucepan over a medium heat. When it starts foaming, add the potatoes and cook until for 5-6 minutes on each side.
Pour in the Essential Cuisine Veal Stock and add the thyme, crushed garlic and some salt and pepper. Cover with a lid and reduce the heat so that the stock is simmering. Remove the potatoes from the pan once they are cooked through and keep warm.
Cut each gem lettuce into quarters. Melt the butter in a pan, add the lettuce and cook for a few minutes, turning occassionally, and season with salt and pepper.
To make the sauce; melt the butter in the pan used to fry the veal, add the port and reduce by half. Make up the Essential Cuisine Premier Veal Jus according to the pack instructions, add to the pan and simmer for 2-3 minutes. Season with salt and pepper and serve with the Veal Wellington, fondant potatoes and pan-fried gem lettuce.
Essential Tip

Take care not to overcook the veal - remember that the meat will continue to cook while resting.