Brown ground beef, drain.Saute veggies in 1 tablespoon olive oil, salt, and pepper for 5-10 min stirring occasionally. If you are short on time, you can skip this step and just throw all the veggies in the slow cooker.Add ground beef, veggies, and rest of ingredients to slow cooker.Cook on high for 4 hours or low for 8.Serve with whole grain spaghetti noodles.