Heat the stock in a pan over a moderate heat. Heat the olive oil in a pan. Add the onions, garlic and celery, and fry gently for about 5 minutes until softened. Add the rice to the pan and turn up the heat. Cook for 1 minute, stirring constantly, until the rice looks slightly translucent. Add the wine and keep stirring - any alcohol flavours will evaporate. Once the wine has cooked into the rice, add your first ladle of hot stock and a good pinch of salt and pepper. Turn down the heat to a simmer so the rice doesn't cook too quickly on the outside. Add ladlefuls of stock, stirring constantly, and allow each ladleful to be absorbed before adding the next, until the rice is cooked but still holds its shape - about 15 minutes. Add the appenzeller and taleggio. Remove from heat and season to taste. Stir in the butter and parmesan. Place a lid on the pan and leave for 2-3 minutes, when it should be nice and oozy.