Pour 200 ml whole milk and 200 ml heavy cream into a saucepan and heat on medium while stirring. Once bubbles start to form around the edges (or it reaches 60 °C (140 °F)-70 °C (158 °F)) remove it from the heat.
Add 2 pasteurized egg yolk, 75 g sugar and 1 tsp cornstarch to a heatproof bowl and whisk until pale and smooth.
Temper the egg mixture by adding 1 ladle of hot milk/cream to the bowl while whisking.
Continue to whisk and gradually add the rest of the hot milk/cream.
Wipe the residue off the pan and then pour the mixture back in through a sieve.
Sift in 1 ½ tbsp matcha powder and then turn on the heat to low/medium low.
Whisk thoroughly until the matcha is incorporated.
Stir continuously using a silicone spatula and scrape the bottom to prevent burning. Once the mixture reaches a thick, custard-like consistency, remove from the heat.
Transfer it to a steel bowl placed in an ice bath. Stir for a few minutes to release some of the heat, then cover the surface with plastic wrap to prevent a skin forming on the top. Leave to cool for 10-20 minutes.
Once cool to the touch, transfer to a wide container with a lid and place in the freezer for 30 minutes. (Tip: It will freeze faster in a wide container rather than a tall one.)
After 30 minutes, take it out from the freezer and whisk for 1 minute. Return to the freezer and churn every 30-45 minutes for 3-4 hours. (Set a timer so you don't forget!)
If the mixture becomes too hard to whisk, switch to a spatula and make sure to scrape down the sides and mix them into the center.Once you've finished churning, freeze for about 2-3 hours. (It can take longer depending on the weather, the temperature of your freezer, and size of your container.)
Remove from the freezer for 5-10 minutes before serving. (This will soften it slightly and make it easier to scoop.)
Enjoy!
Notes
If doubling or tripling the recipe, be aware it will take longer to freeze. You can use multiple containers to shorten the total freezing time.For best results, store in an airtight container and consume within 2 weeks.