Melt the butter in a large pot over medium-high heat until it starts to bubble and turns light golden brown, about 3-5 minutes.

Mix in 8 ounces of mini marshmallows, a splash of vanilla extract, and a pinch of salt. Stir continuously until melted and smooth, about 2 minutes.

Remove from heat and quickly fold in your Rice Krispies cereal until well coated.

Transfer the mixture into a greased 9x13-inch pan and press it into an even layer. It should take about 3-4 minutes.

Allow to cool at room temperature for at least 1 hour, then cut into squares.