1. Finely chop the carrot, the celery and the onion.
2. Heat a pan and sauté them with a little of olive oil.
3. Add the mixed minced meat, the bay leaf and stir.
4. Once the meat has reached a brown colour, pour in the wine and let it reduce.
5. Add the tomato paste, cover with water and cook for at least 30 minutes.
6. Season with salt and pepper, remove the bay leaf and set aside.
7. Clean the mushrooms, slice them finely and cook in a non-stick pan over a medium heat. Set aside.
1. In a saucepan, melt the butter, add the flour and then pour in the milk stirring constantly to avoid lumps.
2. Season with salt and a pinch of nutmeg, then bring to the boil.
3. Cook for only a couple of minutes. Set aside.
1. Grease a baking tray with a little bit of butter and spoon a first layer of béchamel and Bolognese sauce over the bottom.
2. Create the first layer with the lasagne sheets, then cover it with some mushrooms slices and sprinkle with grated Parmesan.
3. Repeat this procedure 5 times, altering layers of Bolognese sauce, lasagne, mushrooms and béchamel.
4. Make sure to leave enough béchamel sauce to completely cover the top layer.
Bake in a preheated oven at 220 °C for 25-30 minutes.
Let the lasagne rest for ten minutes before serving.