In a skillet over medium-high heat, add the olive oil, lean ground beef, diced yellow onions, minced garlic, Italian seasoning, salt, and black pepper. Cook, and brown the beef for 5-6 minutes or until no pink remains. If you have a lot of excess fat from the ground beef mixture, be sure to drain it off before adding it to the crock pot.
Add the cooked ground beef, spaghetti noodles, tomato & basil marinara sauce, crushed tomatoes, and 1 cup of chicken broth to the bowl of the crock pot.
Place the lid onto the crock pot and cook the spaghetti on HIGH for 2 hours or just until the noodles are tender. Be careful not to overcook your noodles, or they will become mushy.
Remove the lid to the crock pot, add the remaining 1 cup of chicken broth, and give the sauce and noodles a good stir with a pasta spoon or tongs to combine all the ingredients.
Top the spaghetti with the grated parmesan cheese and the shredded mozzarella cheese. Replace the lid and cook for another 20-30 minutes or until the cheese is melted.
Remove the lid and sprinkle the chopped fresh parsley over the melted cheese.
Notes
I like to buy the “pot-sized” spaghetti noodles (Mueller’s brand) for this recipe for ease of use. You do not need to break your noodles in half as they are already a shorter length straight from the box. This is not necessary, but I tend to find that my noodles never break very evenly for me, and I always get little pieces that fall.
If you use thin spaghetti or angel hair pasta, check for doneness before the two-hour cook time. The thinner pasta will cook slightly faster than a standard spaghetti thickness. You can also use a short pasta if desired. They may take slightly longer to cook than spaghetti noodles. The shorter kinds of pasta may require a little extra chicken stock added as well to prevent your sauce and pasta from getting too thick. I suggest adding additional liquid ¼ cup at a time until you have a good consistency.
This crock pot spaghetti should be served immediately. The longer the spaghetti noodles cook, the softer they will get as they will continue to absorb the liquid from the sauce.