Very finely dice the chorizo and onion and crush the garlic. Add to a mixing bowl along with the ground turkey, cumin, coriander, cheddar, salt and pepper. Mix together well to combine. Add the egg to the mixture and stir together well.
Divide the mixture into 14 even meatballs.
Heat the olive oil in a large skillet over a medium/high heat. Add the meatballs and cook until well browned all over. Remove from the pan with a slotted spoon and set to one side.
Add the passata and stock to the skillet and bring to the boil.
Reduce the sauce to a simmer, stir well and add the meatballs. Cook uncovered for 5-6 minutes to reduce the sauce, cover and cook for a further 7-8 minutes or until the meatballs and sauce is piping hot and cooked through.