Preheat a skillet over medium heat, and set your slow cooker to “low.” Finely dice the white onion while you wait for the skillet to heat up.

Add olive oil to the frying pan.

Once the oil becomes hot, add the diced onion. Cook until the onions start to become translucent and pick up a bit of color.

Stir in the minced garlic cloves.

Crumble the ground beef into the pan. Don’t worry too much about breaking up the chunks as they cook. Everything is going to fall apart in the slow cooker anyway.

Add in thyme, nutmeg, marjoram, and black pepper.

Mix everything together and allow the beef to cook until it has mostly browned.

Mix in marinar sauce.

Stir in the heavy whipping cream.

Finish the sauce by mixing in chicken bouillon.

Turn the heat off and allow the sauce to rest for about 10 minutes before transferring it to the preheated slow cooker. Be careful not to pour hot sauce into cold stoneware. I’ve cracked them before!

Cover the slow cooker and allow the sauce to simmer for 8 hours. Stir occasionally to prevent burning. When the sauce is ready it will take on a deep color and the house will smell like lasagna. After the sauce has finished cooking, you can season with additional salt if needed.

Preheat the oven to 350F. Using a spiralizer, process the zucchini into noodles and place in a casserole dish. Break apart the longer strands, so that none of them are too long.

Add the olive oil to the noodles. Season to taste and then mix together.

Spread your bolognese sauce over the top of the zucchini.

Top the casserole with shredded mozzarella cheese.

If baking right after cooking the bolognese sauce, then you will only need to heat the casserole in the oven for 15-20 minutes. If you’ve made the sauce ahead of time and it’s been chilled in the refrigerator, then you will need to bake for 30-35 minutes.

Garnish with fresh basil if desired.