In large bowl, combine butters, vanilla and salt using electric mixer. Add sifted confectioners’ sugar one cup at a time, whipping to fully incorporate. Dough will be fluffy but firm; chill briefly if sticky. Shape dough into 1-inch balls. Insert pretzel or stick three-fourths of the way into each ball; place on parchment-lined baking sheets; refrigerate at least one hour or overnight. Place chocolate in small microwave-safe bowl. Microwave 30 seconds on high, stir and continue to microwave in 10- to 20-second intervals, stirring after each until chocolate is melted and smooth. Dip pops in melted chocolate up to the stick, allowing excess chocolate to drip off; sprinkle or dip bottom of pop in garnishes and return to parchment-lined baking sheet to allow chocolate to set or refrigerate pops briefly. Store pops in airtight container at room temperature for up to 1 week.