Heat the oil in a large pan and brown the sausages. Slice and return to the pan. Add the butter and chopped onions and cook gently for a few minutes until soft.
Meanwhile, bring the stock to a simmer in another pan. Add the rice to the onions and continue to cook for 1-2 minutes, stirring continuously. Add the hot stock to the rice a ladleful at a time, allowing the risotto to simmer gently.
Once the stock has been absorbed by the rice, add another ladleful. Continue this process, stirring continuously, until the rice is fully cooked. This should take about 20-25 minutes.
Stir in the Sun-Dried Tomatoes and Black Olives and season.
Great served with a mixed green salad. Try replacing the sausages with chicken.