In a large saucepan over low heat, melt the 1 cup of unsalted butter. Stir occasionally until completely melted.
Once the butter is melted, add 1 package (10 ounces) of mini-marshmallows to the saucepan. Stir continuously until the marshmallows are fully melted and the mixture is smooth.
Remove the saucepan from the heat. Stir in a pinch of sea salt and 1 teaspoon of pure vanilla extract into the melted mixture for enhanced flavor.
Gently fold in the 8 cups of Rice Krispies cereal into the marshmallow mixture until well coated. It’s best to do this gradually to avoid crushing the cereal.
Transfer the mixture into a greased or parchment-lined 9x13-inch baking dish. Press the mixture down evenly using a spatula or your hands (wetting them slightly can help prevent sticking).
Allow the treats to cool at room temperature for about 30 minutes. Once set, cut into squares and enjoy your Classic Rice Krispie Treats!
