Drop your potatoes into a large pot of water and boil until fork tender. While you wait for them, proceed with the meat mixture. If the potatoes cook first, just drain them into a colander and let them steam.

Add a splash of veg oil to a large pan on medium-high heat. Add the meat and break it up with a spatula as it cooks. Let brown for 5 minutes, then drain all but a few tbsp oil from the pan.

Add the onion, garlic, carrot and celery to the pan. Let fry, stirring occasionally, until the veg are softened and the meat's thoroughly cooked (about 10 minutes).

Pour the brandy into the pan. Let simmer until the alcohol boils off and and mixture's mostly dry again. Stir in the tomato paste and keep frying 2 minutes.

Stir the cornstarch into the pan. Once combined, add the beef stock and Worcestershire sauce. Let cook 5 more minutes then give it a taste. Add salt and freshly cracked black pepper to taste, and remove the pan from the heat.

When the potatoes are cooked and well drained, put them back in the pot you boiled them in. Add the milk, butter, a large pinch of salt and a few grinds of black pepper, then give it a mash. If it's too dry, add more milk. If not rich enough, add more butter. You want to end up with mashed potatoes that are oh-so-slightly firm (too wet and they'll run down into the meat instead of sitting nicely on top).

Assemble by lining the bottom of an 18 cm x 24 cm, high-sided baking dish with the meat mixture. Top with the mash, then smooth off the surface. Sprinkle with half of the grated parmesan cheese. Cover tightly with foil and pop the pie into a preheated 400 F oven for 20 minutes.

Take the pie out and remove the foil. Combine the remaining parmesan cheese with the panko and sprinkle it on top. Put the uncovered pie back in the oven on a high broil. Let cook until the top is toasty golden. Before digging in, let the pie cool for 15 minutes so it can set. Serve with a side of beef gravy.