Preheat the oven to 350 degrees F.
Grease a deep 9x13-inch pan.
In the bottom of a long pan, place the lasagna noodles.
Pour hot tap water over the noodles until they are fully submerged, allowing them to soak for at least 30 minutes. Remember to agitate them occasionally so they do not stick together.
In a Dutch oven over medium heat, add the sausage, the beef, the onion, the carrots, and the celery.
Cook until the beef and sausage have browned, about 5-7 minutes.
Add the red pepper flakes and the garlic and cook until fragrant, about 30 seconds.
Drain the grease from the Dutch oven.
Add the crushed tomatoes, the tomato sauce, the water, the tomato paste, the soy sauce, 1/4 cup of the fresh basil, the parsley, the bouillon, the sugar, the vinegar, the oregano, the thyme, the salt, the pepper, and the bay leaf to the Dutch oven.
Cover the Dutch oven and bring the mixture to a boil.
Remove the lid and reduce the heat to low, simmering gently and stirring occasionally until the sauce is reduced but still saucy, about 15-20 minutes.
Add the ricotta, the sour cream, the remaining basil, the nutmeg, the eggs, and 1/2 cup of the parmesan to a bowl, mixing until combined.
In the bottom of the prepared pan, spread 1 1/2 cups of the meat sauce.
Place 4 of the noodles lengthwise over the sauce layer, using part of a 5th noodle to cover.
Spread the noodle layer with 1/3 of the ricotta cheese mixture.
Top the ricotta mixture with 1 cup of the mozzarella and 1/4 cup of the parmesan.
Repeat the layers two more times, starting with the meat sauce and ending with the parmesan.
Top the lasagna with the remaining meat sauce, the remaining mozzarella, and the remaining parmesan.
Tent the lasagna with foil and place the pan on a baking sheet.
Bake for 30 minutes.
Remove the foil and bake until hot and bubbly, about 30 minutes.
Let stand for 15 minutes.
Serve.