Sauté the ground beef over medium heat with fresh garlic, herbs, salt and pepper, stirring periodically to keep the beef as a ground mixture. When meat is cook through, add the onions, green peppers and mushrooms if desired. Then, add enough tomato sauce to keep the mixture well saturated, but of a consistency which is similar to chili (i.e. not too runny). Let the mixture simmer for 20 mins, adding more tomato sauce when necessary to keep the right consistency.
Separately, boil enough lasagna pasta noodles to cover a large oblong baking dish with 2 layers of noodles (we suggest preparing the noodles “al dente” to keep them firm in the lasagna once baked). Rinse with cool water and set aside.
Place a thin layer of the meat sauce mixture onto the bottom of the baking dish. Place 1 layer of lasagna noodles on top of the meat sauce in the pan, and then lay down another layer of meat sauce mixture over the noodles to cover them thoroughly, but not overwhelm them. Next place 1-2 TBSP of ricotta cheese, 3x/row, in a grid pattern over the meat sauce. Put 1 mozzarella slice on top of each pile of ricotta cheese. Then place another pasta layer down over the mozzarella and repeat the layering as above.
Once the final layer of mozzarella is placed on the ricotta, sprinkle the grated Parmesan/Romano cheese over the whole lasagna. Then sprinkle with fresh oregano.
Bake at 350 degrees for 45 minutes. When finished remove the lasagna from the oven and cover it with a dish towel for 10 minutes prior to serving. The lasagna can also be cooked a few hours in advance and reheated when ready to serve.