This is obviously a matcha-centric recipe, so I like to use 1 1/2 tsp. of matcha, but feel free to do 1 tsp. for a lighter coating. Also, I use 1/4 c. of sugar for a slightly sweet flavor, but feel free to add more for sweeter kettle corn!
In a heavy stockpot with tall sides, heat oil over medium-high heat. Add a few popcorn kernels. Once they've popped, reduce the heat to medium and add the butter and the remaining popcorn kernels. Stir.
Sprinkle the sugar over the top. Cover the pot with a lid, and gently shake the pot until most of the kernels are popped, about 1-2 seconds between pops.
Immediately pour the popcorn into a medium-sized, heat-proof bowl or container with a lid. Sprinkle the matcha powder and salt over the popcorn. Place the lid on bowl or container, and shake until the matcha is evenly distributed. (You can also use a large brown paper bag if you don't have a container with a lid!). Let cool (the sugar will be hot!). Happy snacking!