Place diced fontina cheese and milk into a fondue pot or small saucepan. Put over a low heat, stir constantly to melt the cheese and to incorporate the cheese and milk. When melted and combined, remove from heat, stir in the egg yolk and butter until thoroughly mixed in, season with salt and pepper to taste. The mixture should be thick and very creamy. Serve with crusty bread over potato or with asparagus, cauliflower or broccoli. Fonduta is also delicious served with shaved truffles or truffle oil to garnish & Enjoy!