Heat the oil in a large saucepan over medium heat. Add the onion and cook until softened. Add the beef and cook, stirring until brown. Add the garlic, capsicum and spices and stir for 2 minutes.
Add the remaining ingredients and bring to the boil. Reduce the heat and simmer for 15 minutes or until thickened.
To prepare the salsa combine all ingredients.
Roll the meat filling in the tortilla with salsa and lettuce.