For the Bolognese, heat oil in a large saucepan over medium heat. Add onion, cook 5 minutes or until softened. Add garlic and bacon, cook 3 minutes. Add the tomato paste, cook stirring for 1 minute. Add mushrooms, increase heat to high and cook, stirring often for 4 minutes, until tender.
Add the mince, cook, stirring with a wooden spoon until mince changes colour. Add the tomatoes and oregano. Bring to the boil. Reduce heat to low. Simmer, uncovered for 20 minutes or until thickened. Season. Set aside to cool.
Place two flat trays into the oven. Preheat trays and oven 220°C fan forced. Cut 4 x11cm rounds from each sheet of shortcrust pastry. Spoon 1/3 cup of Bolognese into the centre each round. Cut 2x12cm rounds from each sheet of puff pastry. Place over the pies and pleat the edges together to seal.
Brush the top of each pie lightly with beaten egg. Sprinkle with salt and pepper. Cut a small cross in the centre of each. Remove the hot trays from the oven. Arrange pies on trays. Bake 25-30 minutes until golden and puffed. Serve hot with tomato sauce.
Tip You can roughly chop mushrooms by hand, alternately pulse them in a food processor.
Variation Cheesy pies, sprinkle ¼ cup grated cheese over the Bolognese before topping each pie with puff pastry.
Freezer Tip You can freeze the pies at the end pf step 3 for up to 3 months. Bake the pies, from frozen at 200°C fan forced.