Can't get an iced matcha latte right

As trendy as they are currently, I am in love with iced matcha lattes. I recently bought this powdered matcha and tried dissolving about a teaspoon of powder in 1/2 cup of boiling water. I stirred and stirred, and it barely dissolved. I partially gave up, poured in some honey and milk over it, and eventually shook it up a bit. Still didn't really dissolve. Any tips?