This is a variation of the well known Chex Crunch recipe. It makes a nice treat for Valentine's Day, but you can vary the colors of the candy and the flavor of the jello for other holidays if you like.
Stir together chocolate chips and butter in a small microwave safe bowl. Microwave on high for 30 seconds, then stir. Microwave another 30 seconds, stir, if needed continue to microwave for 20 seconds at a time until mixture is completely melted and smooth, then stir in vanilla.
Place chex cereal in a large bowl. Pour the melted chocolate mixture on top of the cereal, and quickly stir. Mix until all the cereal is covered in chocolate. Let sit a couple minutes to allow chocolate to firm up a bit.
Pour powdered sugar into a large (1 gallon) zip lock freezer bag. Add strawberry Jell-O and shake to mix. Place the chocolate covered Chex cereal in baggy with sugar, close and shake until covered. You may need to shake the candy in half batches since bag will probably not hold all the chex at once.
Pour covered cereal back into large bowl. Stir in candies and mix gently so the red still shows up nicely and is not completely covered with white sugar in the finished mix.