Add oil to frying pan, bring to medium heat. Add breakfast sausages and brown. Remove sausages and add onion. Fry until transluscent, stirring regularly. Add eggs and seasonings and scramble. Remove eggs.
Chop sausages into roughly square pieces and add to eggs. Add salsa and mix well.
Fill burrito shell with egg filling and fold. Eat hot or freeze for later. Store leftovers, if any, in fridge.