Butter a 9x13 baking dish or line with parchment paper, then butter.
In a large microwave-safe bowl, add the butter and marshmallows. Microwave for 1 minute, adding 30 seconds as needed until the butter is melted and the marshmallows have expanded and doubled in size.
Stir the marshmallow mixture to combine the marshmallows and melted butter. Add the Rice Krispies cereal and stir gently to coat all of the Rice Krispies with the marshmallow mixture. Pour the Rice Krispies into the prepared baking dish.
Take the now empty marshmallow bag and turn it inside out. Lightly butter it, then put your hand inside the bag and use it to press the Rice Krispies into the baking dish. This protects your hands from getting sticky and the buttered bag allows you to press the Rice Krispie treats without sticking. Ensure that the mixture reaches all of the corners and is pressed gently but firmly into the dish. Allow to rest and cool for 10-20 minutes. Cut into squares.
Meanwhile, add the chocolate chips to a medium-sized microwave-safe bowl. Microwave for 1 minute, then 30 seconds at a time, stirring in between until melted.
Dip each Rice Krispie Treat square into the melted chocolate. Then flip them upside down and place them on a plate or drying rack. If using sprinkles, add the sprinkles to the top of the chocolate-dipped Rice Krispies Treats. Allow the chocolate to fully cool before eating.
Notes
Skip the Stovetop: Use a microwave-safe bowl and heat the marshmallows in the microwave.
Don’t Temper the Chocolate: Tempering chocolate is a method of heating the chocolate so that when it cools it has a glassy, shiny, hard finish. This is a great technique, but not necessary for simple Chocolate Dipped Rice Krispie Treats. Save time and dip the Rice Krispie Treats in melted chocolate. The chocolate will cool and harden, and allow the Rice Krispies to be stacked and stored at room temperature if desired.
Pressing the Mixture into the Dish: Use the empty marshmallow bag turned inside out as a type of “oven mitt”. Butter the now outward-facing inside of the bag, put your hand inside, and press the treats into the dish.
Thicker Rice Krispie Treats: For thicker Rice Krispie Treats, press the mixture into a smaller dish (9x9 or 8x8).
Add Sprinkles While the Chocolate is Warm: Add the sprinkles immediately after dipping the Rice Krispie Treat in the melted chocolate before the chocolate has cooled and solidified to ensure that they stick. My kids love sprinkles. It makes the littlest things feel extra special by just adding the fun, colored rainbow sprinkles.