In a medium saucepan brown the ground beef over medium-high heat until cooked all the way through. Using a slotted spoon, remove the beef into a bowl leaving the fat in the pan.
Add the diced onion and minced garlic to the beef fat and cook until soft and fragrant about 10 minutes. Add the dried herbs to the pan and stir. Add the tomato paste and stir for 1 minute. Mix in the chopped tomatoes and bring to a boil. Season to taste with salt and pepper. Add the beef back to the sauce and stir thoroughly. Set aside.
Melt the butter in a medium saucepan and whisk in the flour. Continue to mix until thick. Slowly add the milk while whisking continuously to avoid any lumps. Add in the nutmeg and stir. Season to taste with salt and pepper.
Layer the lasagna sheets until the bottom of your baking dish is covered. Ladle some of the beef sauce onto the pasta and spread to cover. Top the sauce with a layer of mozzarella and then a layer of the béchamel. Sprinkle with some chopped basil.
Continue layering until the baking dish is full and the sauces and pasta are used up. Top with the remaining 1/2 cup mozzarella cheese. Chop the remaining basil and scatter over the top.
Bake uncovered for about 30 minutes, or until the lasagna noodles are cooked and the cheese is brown and bubbling. (If the cheese starts to darken too much, cover the pan loosely with aluminum foil.) Remove from oven and serve.
You can substitute standard lasagna noodles (instead of oven-ready), just be sure to cook them according to package directions before layering them in the baking dish.