With a mixer, beat butter, peanut butter, marshmallow fluff, vanilla extract, and salt together until light and fluffy, about 2-3 minutes.

Add in powdered sugar, 1/2 cup at a time. (If after 1 cup of powdered sugar, the frosting is a thinner consistency than you like, add in the last 1/2 cup; I prefer a thick frosting, so I used the full 1 1/2 cups ).

Add heavy cream, and beat until frosting is well combined.

In the microwave at 50% power, melt 1/4 cup of semi-sweet chocolate in 30 second intervals, stirring after each hit. Once the chocolate has melted, allow it to cool slightly, about 5 minutes.

While chocolate is cooling, open each pudding cup and place a layer of marshmallows (about 5 or 6) on top of the pudding.

Pipe on a layer of frosting over each pudding cup.

Place 3 marshmallows on top of the frosting and drizzle with melted chocolate (either with a spoon or with a piping bag).

Refrigerate until ready to use. Enjoy!