Tea Soda

Ingredients

Loose-leaf tea — I usually use Vahdam’s rose black tea, but try experimenting here; genmaicha, matcha, or jinxuan oolong could all be good choices
Powdered sugar
Club soda — I usually use Q Mixers or Fever Tree

Cold brew 3-4 tablespoons of tea for a few days. I prefer to use the Hario cold-brew bottle, but you could use a mason jar instead.
Make a 1:1 tea simple syrup by boiling 1 cup of the cold-brew tea with 1 cup of sugar. Keep the heat as low as you can to avoid crystallization while still dissolving all the sugar. Tea simple syrup should last in the fridge for a few weeks.
Mix with soda water. Use just enough to cover the bottom of a tumbler; about a teaspoon should be enough.