2Prepare the Bolognese sauce: In a large pan, sauté chopped onion, minced garlic, and grated carrot in a little oil until soft.
3Add the minced meat and cook until browned.
4Add salt, black pepper, paprika, mixed herbs, and the tomato cube. Stir well.
5Add the chopped tomatoes, water, and bay leaves. Simmer for 20-30 minutes until the sauce thickens.
6Prepare the béchamel sauce: In a saucepan, melt the butter over medium heat.
7Add the flour and stir constantly for 2-3 minutes.
8Gradually add the milk, whisking to avoid lumps.
9Season with salt and black pepper. Cook until the sauce thickens.
10Assemble the lasagna: In a baking dish, spread a layer of Bolognese sauce, then a layer of lasagna sheets, then a layer of béchamel sauce. Repeat the layers, finishing with béchamel sauce on top.
11Sprinkle with grated cheese if desired.
12Bake in the preheated oven for 35-40 minutes until golden and bubbling.
13Let the lasagna rest for 10 minutes before serving.