Combine all ingredients in the slow cooker and cook on low for 5 hours. This will be your basic burrito filling minus the eggs. You can start it at night to be ready first thing in the morning. Or cook it whenever you have the time, allow it to cool and refrigerate for up to 5 days.
When you're ready for your burritos, warm the filling if needed and scramble 1 egg per burrito. Spread some filling and egg on your large flour tortillas, add some shredded cheese and salsa if you like and fold them up.
Note - you'll also need large flour tortillas and at least one egg per burrito. Cheese, salsa and anything else you like on your burritos is optional.