Place ⅓ cup of cereal in a small bowl and pour milk evenly overtop. Allow to soak for 20 minutes.

Meanwhile, chop white chocolate into small pieces and place in a microwave-safe bowl. Microwave for 30 seconds, stir, then return to the microwave, heating in 15-second increments and stirring well in between until melted and smooth. Allow to cool until no longer warm, but still melted.

Place butter in a separate, large mixing bowl and use an electric mixer to beat until smooth and creamy. Once chocolate is cooled, drizzle it in with the butter and stir until smooth and well-combined.

Gradually add powdered sugar, stirring until completely combined.

Add salt and stir well.

Pour the cereal and milk through a fine mesh strainer into a measuring cup. Use a spatula to squeeze out as much milk as you can and discard cereal.

Measure out 2 Tablespoons of milk and add to the frosting bowl. Stir on low-speed until smooth and incorporated.

Grind remaining 2 Tablespoons of fruity pebbles into fine crumbs (I use my small food processor). Add to the frosting and use a spatula to stir in until smooth and well combined.

Pipe or spread frosting as desired over cooled baked goods.