Preheat the oven to 200C, fan-forced. Grease a 1L (4 cup) round pie dish. Peel the potato and cut into 1cm chunks. Cut the carrot into 1cm chunks. Coarsely chop the onion. Crumble 1 stock cube* into a heatproof jug, add 250ml (1 cup) boiling water and stir to dissolve.
Step 2 — Start filling
Heat 1 tsp olive oil in a medium deep frypan over medium-high heat. Cook the bacon, stirring, for 4-5 mins until crisp. Add the beef mince and cook, breaking up the lumps with a spoon, for 3 mins or until browned. Add the potato, carrot and onion and cook, stirring, for 5 mins or until softened. Add 1 tbs plain flour and cook, stirring, for 2 mins or until golden.
Step 3 — Simmer filling
Stir the stock, worcestershire sauce and half the tomato paste* into the beef mixture and bring to the boil. Reduce the heat to low and cook, covered, for 15 mins or until the potato is tender. Remove the pan from the heat. Taste, then season with salt and pepper.
Step 4 — Prep pastry
Meanwhile, melt 20g butter and 1 tbs olive oil in a small saucepan over medium heat. Lay 1 filo sheet on the bench (put it on a clean tea towel to prevent it sticking to the bench, and cover the remaining filo with a damp tea towel while you work so it doesn't dry out). Brush with the butter mixture, then top with another filo sheet. Repeat with 5 more filo sheets.
Step 5 — Assemble pie
Use the filo stack to line the base and side of the pie dish. Using scissors, trim the filo to the rim of the dish. Spoon the filling into the pastry case. Lay 1 filo sheet on the bench and brush with the butter mixture. Top with another filo sheet, then repeat with 1 more filo sheet*. Fold in half, put on top of the filling, then trim to a circle that fits in the dish.
Step 6 — Bake and serve up
Fold the side of the filo pastry case down over the circle to cover. Cut a cross in the centre of the pie top, then brush with the remaining butter mixture. Bake for 35-40 mins until the pastry is golden. Stand for 5 mins. Serve immediately to prevent the pastry becoming soggy. Enjoy! Serves 3-4.