2. Melt the egg yolk and sugar with electric egg beater.
3. Beat the yolk to white.
4. Heat the milk and cream until it is about to boil, slowly pour it into 2, while stirring.
5, add yogurt, mix well and refrigerate to about 5 degrees.
6. Put the ice cream machine in the freezer for more than 8 hours in advance, take it out, press the start button, and pour the ice cream liquid.
7. After the ice cream machine stirred 10 minute, the ice cream liquid began to solidify slowly.