In a microwaveable bowl, combine chocolate chips, butter/oil, peanut butter and vanilla. Microwave for 1 minute, then stir. Continue heating for 30 second intervals and stirring until the chips are melted and all combines well. It should be warm, but not too hot to handle.

In a large bowl, combine the cereals. Pour the chocolate mixture on top and stir until it evenly coats all of the cereal.

Working in batches, put about a cup of powdered sugar in a large ziplock bag and scoop a few cups of the cereal mixture in. Seal the bag and shake it until the cereal is coated with powdered sugar. Pour it out on a baking sheet in a single layer and let it cool to room temp. Continue until all of the cereal mixture is coated in powdered sugar.

Once cooled to room temp, you can put it in a bowl to serve or store in a sealed container for up to a week at room temp or in the fridge if you like a crunchier texture.