Mix the flour with a little salt and cayenne pepper.
Cut the fillets into small cubes and turn them in the flour. Heat the oil in the pan and fry the garlic and onion (cut into thin rings) until they are translucent. Remove the garlic and onion from the pan and then fry the fillet cubes until golden brown.
Add the garlic and onion cubes again along with the wine and the stock. Season to taste with saffron and pepper. Bring to a boil and then cover and simmer for about 15 minutes.