Begin by mixing two tablespoons of granulated sugar with the matcha green tea powder in a bowl.
In a separate bowl, mix the remainder of the granulated sugar with the egg yolks. Then add the matcha powder and sugar and stir well to form a thick green paste.
Gently heat the milk in a medium saucepan without letting it boil to a low simmer. Remove from the heat and mix a small amount of the warm milk with the matcha green tea mixture until it becomes a smooth paste.
Gradually add the milk to the rest of the matcha green tea paste while keeping the mixture smooth and then return to the heat.
Before the mixture boils, remove again from the heat and then strain the whole mix through a fine sieve to remove any impurities. Leave the mixture to cool before the next step.
Whip the double cream lightly and then fold into the matcha green tea mixture.
Once the mixing is complete, set in a large container and put in the fridge to cool down for a few hours.
Finally, you can put the container in the freezer. To stop ice crystals forming in the ice cream, be sure to remove every few hours and mix the ice cream vigourously. Repeat this a few times as it freezes to guarantee a delicious, perfectly smooth ice cream.