Place marshmallows and butter in a large pot and heat on medium/low heat stirring frequently until completely melted and smooth.
Remove from heat and pour in rice krispies.
Fold them in mixing until all the cereal is coated with the marshmallow mixture.
To make the treats heart shaped
Option 1- Press the cereal mixture into a parchment-lined 13x9 inch pan and allow it to cool completely. Once cooled remove the treats from the pan and cut out hearts with a cookie cutter.
Option 2- Line your surface with wax paper or parchment paper. Butter your hands and the cookie cutter. Working quickly press cereal mixture into the cookie cutter to form hearts.
Continue until all the cereal mixture is used.
To decorate the hearts
Working with one color at a time place candy melts in a microwave safe bowl. Microwave in 30-second increments stirring in between until melted and smooth.
If necessary to create a smooth texture add in shortening 1 tsp at a time until desired consistency is reached.
Place the melted chocolates in a piping bag and cut off the end creating a small hole.
Pipe melted chocolate around the edge of each treat outlining the heart shape.
Then fill in the heart with melted chocolate. Smooth with a knife to create an even finish.
Allow cooling completely.
Repeat with additional colors until all treats are coated.
To add sayings to the conversation hearts
Use an edible marker to write on the hearts, if you make a mistake you can wipe it off with a moist paper towel.
Then melt pink or red candy melts and place them in a piping bag.
Cut a small hole in the end and trace letters with the melted candy.
You can also freehand the words if you’d like.
Allow cooling.
Store in an airtight container.
Notes
Store leftovers in an airtight container. Number of hearts will be determined by the size of your heart cookie cutter.