Skin and bone the lamb loin.

Finely chop the onions.

Sweat the chopped onions in 2 ounces of drippings until softened.

Add finely chopped mushrooms and cook for 2 minutes.

Incorporate breadcrumbs, laverbread, and chopped parsley into the mixture.

Mix the ingredients with a little milk to achieve a smooth consistency and season to taste.

Stuff the loin with the prepared mixture.

Tie the stuffed loin securely and season it.

Seal the loin with melted drippings.

Roast the loin in a 430°F (220°C) oven for 30 minutes.

Allow the roasted loin to cool and drain any excess juices.

Roll out the shortcrust pastry into a rectangle, approximately 5/16 inch thick.

Spread the remaining stuffing evenly over the pastry, leaving a 2-inch margin on all sides.

Place the cooled loin onto the pastry.

Brush the pastry margin with egg wash.

Completely envelope the meat with the pastry and seal it tightly.

Turn the pastry-wrapped loin over and place it onto a greased baking sheet, ensuring the folds are underneath.

Brush the top with egg wash and decorate as desired.

Bake in an oven preheated to 425°F (220°C) for 30 minutes, or until the pastry is golden brown.

Garnish with fresh parsley and sliced tomatoes.

Serve warm with braised leeks, jacket potatoes, and brown sauce.