Line a parchment paper on an 8x8 pan.

Add the butter and the marshmallows in a saucepan and melt in a low heat.

Stir the mixture until the marshmallows and the butter melts.

Add the peanut butter and continue to stir the mixture.

Once all the ingredients are melted and combined well, take off the stove and stir in rice crispies.

Take the rice crispies to the pan and gently press them down.

Let the bars cool down for 1 hour at room temperature, then you can put it into the fridge for 1 hour.

Melt the dark chocolate in the microwave with pauses of 10 seconds (Be careful not to burn)

Pour the chocolate on top of the crispies and let it cool down for 1 more hour in the fridge.

Take them off the fridge and cut them into 9 pieces. (if the chocolate is too hard, you can heat your knife and then cut it.

You can put some sea salt on the top of the treats.