Generously grease a standard 8"x8" pan and set aside.
In a medium sized saucepan set over medium-high heat, melt the butter. Add 2 cups of the marshmallows and stir occasionally until they are completely melted. Add the cookie butter and salt and mix until everything is uniform.
Turn the stove off and take the saucepan off of the heat. Stir in the puffed rice cereal and the remaining 1 cup of marshmallows.
If desired, you can melt ½ cup of the pumpkin cookie butter with 1 cup of chocolate chips and spread it on top of the bars.
Allow the bars to cool completely before cutting and serving. Bars should be stored in an airtight container at room temperature and will last for about a week.
Recipe by Mandy's Recipe Box at https://mandysrecipeboxblog.com/pumpkin-cookie-butter-rice-krispy-treats/