Warm the milk. In a medium saucepan, heat 4 cups of whole milk over medium-low heat until it is steaming, around 160 to 170 degrees Fahrenheit. Do not let it boil.

Dissolve the gelatin. Remove the pan from heat. Sprinkle 3 tablespoons of unflavored gelatin powder over the surface of the warm milk. Whisk gently and steadily for 1 to 2 minutes until completely dissolved and no granules remain. This step matters, so take your time.

Add the matcha and flavor. Whisk in 2 teaspoons of matcha powder, 2 tablespoons of maple syrup, and ½ teaspoon of vanilla extract. Continue whisking until smooth and no clumps remain.

Pour and cool. Pour the mixture into a lightly greased 8x8 inch baking dish or silicone molds. Let it cool on the counter for 20 to 30 minutes.

Refrigerate. Move the dish to the refrigerator for at least 4 hours, or overnight for the best texture.

Cut and store. Once fully set, cut into 1-inch cubes. Store covered in the refrigerator for up to 5 days.