2) In medium saucepan saute the pepperoni over a medium heat until crispy. Remove from the heat and drain on a paper towel.
3) Pour 250ml of the tomato sauce into a 25cm by 32cm by 8cm deep baking tin or dish. Layer lasagna sheets on the bottom of the tin, overlapping by 1cm.
4) Layer 1/4 of the ricotta, 1/4 of the mozzarella, 1/3 of the sausage, then sprinkle generously with 1/4 of the Parmesan, add 120ml of the tomato sauce and 100g of pepperoni. Add a layer of lasagne. Repeat this 2 more times.
5) On the very top sheet, top with the remaining ricotta, mozzarella, tomato sauce and pepperoni, and dust with Parmesan. Bake for approximately 45 minutes. Remove from oven; leave to sit for 15 minutes. Cut and serve immediately.
For the tomato sauce:
1) In a medium saucepan, heat the olive oil. Add the onion and cook over a medium to low heat until transparent. Add the garlic and cook until almost brown. Then add the tomatoes and cook for 1/2 hour over a low to medium heat.
2) Add the basil and oregano and continue to cook for another 1/2 hour. Season, to taste, with salt and pepper, cool and store in the refrigerator until ready to use.