Prep time: 35 min | Ready in: 7 hours
3 packages unflavored gelatin
2 cups granulated sugar
1 cup powdered sugar
1-1/2 cup dark chocolate chips
Red food coloring
A candy thermometer
9×13-inch cake or jelly roll pan
6-ounce plastic squeeze bottle (cut off enough of the tip of the lid so the opening is about 1/4 of an inch across)
Line the inside of the pan with tin foil, then coat well with cooking spray.
In a large mixing bowl, combine a 1/2 of a cup of cold water with the packets of gelatin and allow to sit until gelatin forms, about 15 minutes.
In a medium saucepan on medium heat, combine the sugar and 1/2 of a cup of water, then stir until sugar has dissolved—about 3 to 5 minutes. Increase heat to bring mixture to a low boil, and continue to boil until the temperature reaches 240 degrees F on a candy thermometer—about 12 to 15 minutes.
Remove from heat.
Slowly pour sugar mixture into the bowl with the gelatin, simultaneously using a mixer on low. Gradually increase speed to high and continue whipping until the mix is very thick, about 10 to 15 minutes—imagine the consistency of pourable taffy.
JUST A REMINDER: You need to do this pretty quickly. You only have about 3 to 4 minutes before the batter starts to set and the hearts don’t come out as well.
Pour all but 1 cup of the mixture (you’ll need to save some for the red hearts) into the pan.
Add red food coloring to remaining cup of batter and stir well. Pour red batter into the plastic squeeze bottle. It helps to pour from several inches up so that the batter is thiner by the time it reaches the bottle opening.
Starting in one corner of the pan, pipe a row of red dots along the long side of the pan. Make sure your first dot is tightly in the corner (see pic of finished hearts below for best placement), and leave about a half inch of white space at the very end of your row. Each dot should be about a half of an inch in diameter.
Pipe a second row about 1 inch away from the first line (the white space is what will get dipped in chocolate), and repeat this process until you’ve reached the other end—you’ll be able to do 4 or 5 lines. You want your last line to be about one inch from the other end.
Start at the top of your first row and drag a toothpick through the middle of the dots, going in the same direction that you placed the dots. Repeat with remaining rows.
Let the marshmallow sit for about 6 hours, uncovered, until completely set.
Cover a surface larger than the marshmallow slab with powdered sugar and flip the cake pan over so that marshmallow lands on the dusted surface. You have to do it quickly, and it’s going to kick up some “dust,” so just prepare yourself. (It’s all part of the fun, right?)
First, cut marshmallows in long strips so that you have white space on one side, hearts on the other.
Then slice into smaller squares or rectangles, 2 or 3 hearts per piece.
Dust all sides of marshmallow pieces with powdered sugar and place on a cookie rack. Now, if you’d like to dip them in chocolate…
Cover a cookie sheet with parchment paper and set near your stovetop.
Over high heat, bring 1 to 2 inches of water to a boil in a medium saucepan. Reduce heat to low and place a bowl in the saucepan. Be sure the water doesn’t get displaced enough to spill over into the bowl.
Pour in chocolate chips. Stir until completely melted.
Dip the non-heart half of each marshmallow into the chocolate, allowing excess chocolate to drip off (I even shake it a little), then place on the cookie sheet with parchment paper, heart side up.
Refrigerate chocolate-dipped marshmallows until chocolate hardens, about 20 minutes. Store refrigerated in Ziplock bags.