Line a 9x9 inch baking dish with parchment paper, leaving some overhang on the sides. This will make it easier to lift the treats out later.

In a large saucepan over low heat, melt the butter. Stir occasionally to prevent burning.

Once the butter is melted, add the mini marshmallows. Continue stirring until the marshmallows are completely melted and the mixture is smooth. This should take about 3-5 minutes.

Remove the saucepan from heat and stir in the vanilla extract and salt. This enhances the flavor of the treats.

Add the Rice Krispies cereal to the melted marshmallow mixture. Stir gently but thoroughly until all the cereal is evenly coated. Be careful not to crush the cereal.

Pour the mixture into the prepared baking dish. Using a spatula or your hands (lightly greased), press the mixture down evenly into the dish. Make sure it’s compact for better cutting later.

Allow the treats to cool at room temperature for about 30 minutes. Once set, lift the treats out of the dish using the parchment paper.

Cut into 12 squares or rectangles using a sharp knife. Wipe the knife with a damp cloth between cuts to prevent sticking.