Kitchen Sink Rice Krispie Treats

Prepare a 9×13 baking pan with nonstick cooking spray and parchment paper. Extend the parchment paper up the sides of the pan to easily remove the rice krispie treats from the pan.
In a large saucepan on the stovetop over medium-low heat, melt the unsalted butter. Add in 20 ounces of mini marshmallows and stir until the marshmallow mixture is melted and smooth. Remove the saucepan from the heat.
Stir in the vanilla extract and salt. Then, fold in the crispy rice cereal, additional mini marshmallows, chopped salted pretzels, and chopped salted ruffle potato chips until well coated in the melted marshmallow mixture.
Spread half of the rice krispie treat mixture into the prepared baking pan. Moisten your hands with water, and gently press the mixture into the pan creating an even layer.
Sprinkle ½ cup of the M&M candies, ¼ cup of the mini M&M candies, and 2 tablespoons of the mini chocolate chips over the rice krispie treat layer.
Spread the remaining rice krispie treat mixture evenly over the chocolate. Lightly moisten your hands with water, then gently press the mixture into the pan to create an even layer.
Press the remaining pretzels, potato chips, M&Ms, mini M&Ms, and mini chocolate chips into the rice krispie treats. Sprinkle with flaky sea salt.
Allow the rice krispie treats to set in the pan for 1 hour before removing and cutting into squares. For easier slicing, you can also chill the bars for 30 minutes.