Add Chex, pretzels, M&M’s, Reese’s hearts, Swedish Fish, marshmallows, and gummy bears to a large bowl. Toss to combine.
Place white chocolate in a microwave-safe bowl and microwave in 20-second intervals, stirring between each, until fully melted and smooth.
Let the melted chocolate cool for 2-3 minutes to thicken slightly and then drizzle it over the snack mix in the bowl.
Toss gently to create light clusters and then serve immediately.
Keep leftovers to an airtight container at room temperature for up to 3-4 days.