Pour Rice Chex cereal into a large bowl or clean brown paper bag and set aside.
In a large microwave-safe bowl, combine sweetened condensed milk, melted butter, and white chocolate or cream cheese chips.
Microwave the mixture in 30-second increments, stirring in between, until the chips are fully melted and smooth.
Mix in the pistachio pudding powder, then add vanilla and salt.
Pour the pudding mixture over the cereal and toss until evenly coated.
Add powdered sugar and toss again to coat evenly.
Allow the treat to cool completely before storing in an airtight container.
