Lay the phyllo tart shells out on a serving platter.
Melt the butter in a medium skillet over medium heat. Add the pistachios and toast in the butter, stirring, until they have a nutty aroma, about 2 minutes. Add the honey, sugar, cinnamon and salt and cook, stirring, until thick and bubbling, 1 to 2 minutes.
Use two small spoons to scoop the pistachio filling into the shells. Cool to room temperature before serving.