You can get these items at Costco:
Matcha tea
Kirkland 8 fl oz Organic whole milk
(no refrigeration required. I kept these milk cartons stocked in my pantry. No more tossing away unused refrigerated milk! And I can easily have milk for making my matcha tea and other creamy soup.)

Ingredients for two cups of matcha latte:
1 teaspoon matcha powder
Two 8 oz cartons of Kirkland organic whole milk
Add brown sugar or honey to your taste
A tiny bit of cinnamon powder (optional)
How to make it:
Empty two cartons of Kirkland 8 oz whole milk into a small pot.
Heat up the milk until it is WARM. It will mix better if you add the matcha when the milk is warm but not too hot. Add one teaspoon of matcha powder and a little bit of sugar into warm milk and keep stirring them with milk in the pot with a whisk while continuing to cook it over medium heat.
I just use a regular whisk to make the matcha latte. Yes, you don’t need a special device for making matcha tea but the following kitchen tool will work just as well.
I usually add brown sugar or you can add honey instead. Keep stirring them together until all ingredients are mixed well and until the latte is nice and hot.
I don’t like it too sweet so I only add a little bit of brown sugar to the taste. Then I just keep stirring them together as the latte gets hotter until it is hot enough for a tasty hot drink!
I am telling you and my daughter said that too: It tastes better than Starbucks’ matcha latte. You can save a lot of money by making this yourself! And I can bet that it is healthier than drinking a syrupy matcha latte from the Starbucks!

I already drank up the matcha tea I just made. I will remember to add some photos that show the making process and a photo of my home-made matcha latte next time I make it.