Melt the butter in a large pot over medium heat. Add sweetened condensed milk and stir until bubbly, about 30 seconds. Stir in a splash of vanilla and pinch of sea salt.

Reduce heat to medium low and stir in the marshmallows. Continue to stir until marshmallows are completely melted. Add a few drops of green food coloring and stir to combine.

Remove from heat, and add rice krispies and the last cup of mini marshmallows (if using), stirring to combine.

Transfer the treats to a greased 9 x 13 inch pan and gently spread out. (You can grease your hands with cooking spray to make this easier).

While the treats set up, melt the chocolate and coconut oil in the microwave or a double boiler into smooth. Place a ¼ cup of the chocolate mixture in a sandwich size ziplock bag. Put the remainder in a glass measuring cup.

Slice the treats into 16 slices and place them on waxed or parchment paper. I do them tall and skinny, so four cuts on both the long and short ends.

Dip the treats into the chocolate, covering about ¼ of the top. Scrape off any excess chocolate, and lay on waxed or parchment paper, with the flatter side facing up.

Decorate the faces. This is the really fun part! Cut a tiny snip out of the corner of the bag of chocolate so you have a make-shift piping bag. Place two dots of chocolate on each treat for the eyes. While the chocolate is still wet, place the googly eye on top so it sticks. Pipe some stitches for a mouth, and give your Frankenstein some eyebrows. Allow the treats to dry before eating.