Cover a 13×9 baking dish with parchment paper and keep handy, ready to fill.
In a large, deep skillet, melt the coconut oil and the marshmallows together over low heat, stirring almost constantly. Do not let burn.
Once the mixture is smooth, add the salt, and then stir in the rice cereal, coating all the cereal pieces.
Turn off the heat, and sprinkle in the white chocolate, stirring gently but quickly.
Move the pan over to the parchment-lined dish and scrape in the mixture, pressing it down gently. If the mixture is too sticky, moisten your fingers with water, or use a rubber spatula.
Allow the mixture to cool for 20 minutes before cutting into squares and serving.