Let's Make Bolognese Sauce.
Heat a skillet and put some Olive oil. Add mire poix carrot, celery, Onion, and garlic and sauté for some time. Add minced meat and mix well. Cook it for some time in medium heat and add peeled tomatoes and mix well. Add some salt and black pepper as per taste. Add Oregano and Parsley then stir well. Now cook for some time, when it's done keep aside.

Now let's make White Sauce.
Heat a skillet and put butter and let it melt. Now add flour and whisk and cook in low heat. Cook the roux for some time and remove from heat before it turns color. Add milk and whisk well. Now add salt and pepper as taste. Let it simmer for some time. It should be thick but not too thick.

Fix the bayleaf on onion by piercing cloves. and gently put it in sauce for some time so that no impurities be present in sauce otherwise strain the sauce. Now add a pinch of nutmeg powder by grating. Now keep it aside.

Take a medium Lasagna baking pan that can hold 2 sheets. Put some olive oil in the pan and spread it on all surface. Now put some white sauce in it and spread it.

Put 2 sheets of Lasagna on it pararelly and put some bolognese sauce on it. Spread the sauce on the surface each time. Now spread some white sauce on it and some parmesan cheese. Now put pasta sheets and sauces and cheese on itas before. Repeat it and make till 3 layers of sauce and now put again pasta sheets on it and add white sauce on it.