Warm the milk and cream gently to 175°F/80°C and cool to 80°F/27°C. Stir in the rennet. Cover and leave to stand until it forms a firm jelly which may take 8–12 hours. Break up the jelly and put into a sieve to let the whey drain off. Put the curd into a dish with the beaten egg yolk and sugar to taste, and mix well. Serve with fresh cream and more sugar.