To make the slow cooker meatballs: In a large bowl, combine sausage meat with ground beef, parsley, 1/2 cup Parmesan, 1/2 tablespoon Italian seasoning, and black pepper. Using a spoon or cookie scoop, form golf-sized balls and set them aside on a plate.
In a skillet over medium-head, add a tablespoon olive oil and quickly brown meatballs on all sides. Transfer the meatballs to the slow cooker insert.
Add the sauce ingredients (tomato sauce, beef or vegetable stock, Italian seasoning, Cayenne pepper, garlic powder, onion powder, black pepper, 1/2 cup Parmesan, and parsley) over the meatballs and give a good stir. Cover and cook on high for 2-3 hours or low for 4 hours.
Serve the slow cooker Italian meatballs hot, with freshly grated Parmesan cheese on top of cauliflower rice, or zucchini noodles. Enjoy!
Use a blend of meats for the best flavor. We use beef and Italian sausage (pork) because is very accessible at a reasonable price, with the benefit of having the sausage meat already seasoned, which is good if you don’t have all the spices on hand. You can also try to mix beef with veal and pork or make your meatballs with chicken and/or turkey.
You don’t need extra-lean meat, stick with 80 or 85% lean, otherwise, the meatballs will end up dry.
Shape the meatballs with lightly greased hands. This way the meatballs don’t stick to your fingers.
You might have to brown the meatballs in batches since you’ll have no chance at a good sear if the meatballs are crowding the skillet. Searing the meatballs before slow cooking gives a nice crust that is full of flavor. Plus, it helps the meatballs stay together while cooking in the slow-cooker.