Use a large pasta pot and melt the butter over medium heat.
After the butter has melted, add the 8 cups of the mini marshmallows. Stir continuously over medium heat so that the marshmallows won't burn.
Once the marshmallows have melted, turn off the heat, and add the cereal and salt. Stir a few times, until mixed, and then add the remaining 2 cups of marshmallows, white chocolate chips, and crushed candy cane. Stir until completely combined.
Pour out the mixture into a greased or parchment lined 9x13 pan. (You can always use a smaller pan for thicker bars.) Press it down into the corners and let cool for about 15 minutes before cutting.