Grease or line molds with wax paper for easy removal.
In a large saucepan, melt the butter over low heat until it’s completely melted and fragrant.
Add the marshmallows to the melted butter and stir gently until they are fully melted and glossy, creating a smooth mixture.
Remove the mixture from heat and immediately add the rice cereal, folding it in with a spatula until evenly coated.
While still warm, spoon the mixture into the prepared molds, pressing lightly to compact it and smooth the surface.
Allow the treats to cool in the molds for about 10-15 minutes until set.
Carefully remove the shaped treats from the molds and place them on a piece of wax paper.
Melt the chocolate in a microwave or double boiler until smooth and glossy.
Pour or pipe the melted chocolate onto small parchment paper or directly onto the top of each pumpkin to create a tiny stem shape.
Let the chocolate stems harden at room temperature or in the refrigerator for about 10 minutes.
Once the stems are firm, position them on top of each pumpkin treat, finishing with a festive Halloween presentation.
Serve your adorable pumpkin Rice Krispie treats or store them in an airtight container for later enjoyment.