Combine crushed tomatoes, oregano, red pepper flakes and olive oil in the bowl of a slow cooker. Stir in onion, bell peppers and Italian sausage. Season with salt and pepper. Cook on low 6 hours.
Stir basil into the cooked sausage and peppers. Serve warm on toasted hoagie rolls.
Recipe by 5* trending recipes with videos at https://food.theffeed.com/2021/06/23/slow-cooker-sausage-peppers/