Prepare your pan: Line a 9x9 baking pan with parchment paper or lightly grease it.
Melt the butter: In a large saucepan over low heat, melt the cannabis butter and regular butter.
Add marshmallows: Stir in the marshmallows and cook on low heat until fully melted and smooth.
Add flavorings: Stir in vanilla extract and salt if using.
Mix the cereal: Remove from heat and fold in the crispy rice cereal until evenly coated.
Press into the pan: Transfer the mixture to the prepared pan and gently press it down with a spatula.
Cool and slice: Let the treats cool for 20-30 minutes, then cut into squares and enjoy.