1. Prepare the Crust:

1. In a large bowl, cream together butter and sugar until light and fluffy. Beat in egg and vanilla extract.
2. Gradually mix in flour and salt until dough comes together. If desired, add red food coloring for a pink or red hue.
3. Divide dough in half. Shape each half into a log, then flatten one side to form a heart shape. Wrap in plastic and chill for at least 2 hours.
4. Preheat oven to 350°F (175°C). Slice chilled dough into 1/4-inch thick slices and place on baking sheets. Decorate with sprinkles if desired.
5. Bake for 10-12 minutes or until edges are lightly golden. Cool on wire racks before serving.