Step 1

To prepare meatballs: Lightly beat eggs in a large bowl. Stir in breadcrumbs, 1/2 cup onion, cheese, parsley, garlic, salt and pepper. Add beef, pork (or sausage) and veal; gently mix until combined (do not overmix). Using 1/4 cup for each, make 16 meatballs and place in a 6-quart slow cooker.

Step 2

To prepare sauce & spaghetti: Heat oil in a large skillet over medium heat. Add 1 cup onion and cook, stirring occasionally, until beginning to brown, 3 to 5 minutes. Add garlic, Italian seasoning and crushed red pepper; cook, stirring, for 30 seconds. Add wine and boil for 1 minute. Add crushed and diced tomatoes and bring to a simmer. Pour the sauce over the meatballs.

Step 3

Put the lid on the slow cooker and cook on High for 4 hours or Low for 8 hours.

Step 4

30 minutes before you're ready to eat, bring a large pot of water to a boil. Cook the spaghetti until just tender, 8 to 10 minutes or according to package directions.

Step 5

Spoon any fat off the sauce; add oregano. Serve the meatballs and sauce over the spaghetti with extra Parmesan, if desired.