Quick, easy, and such a crowd-pleaser!
Make Rice Krispies Treats and, while the mixture is still warm, use a large heart-shaped cookie cutter to cut them out. If you can’t find a cookie cutter of the right size, draw a heart on cardboard and use it as a template. Just lay it on the sheet of Rice Krispies Treats and trace around it with a knife.
For even more Valentine's Day fun, add a few drops of red food coloring to the marshmallow mixture for a pink version of the sticky treat, or press red and pink candy into the top.