1. Preheat oven to 350°F (180°C). Line baking sheets with parchment paper or silicone baking mats. Set aside.
2. Combine the flour, baking soda, baking powder and salt in a medium sized bowl and set aside.
3. Cream the butter and sugars together in a large mixer bowl on medium speed until light in color and fluffy. You should be able to see the change in color happen and know it’s ready.
4. Add the egg and mix until well combined.
5. Add the vanilla extract and mix until well combined.
6. Add the dry ingredients and mix until the dough is well combined. It will be thick and shouldn’t be sticky. Do not over mix. Once it’s well combined, use a rubber spatula to help it come together to form a more cohesive ball.
7. Color the cookie dough with some green gel icing color. The less the better. You don’t want to add too much more moisture or your cookies will spread too much.
8. Create 1 1/2 tablespoon sized balls of cookie dough. Gently roll into a ball, then set the balls on the baking sheet. At this point, you can add a red heart sprinkle to the top of the cookie dough ball if you like. You could also waiting and attach them after baking if you want to be able to place them in a particular spot.
9. Bake cookies for 7-8 minutes. The cookies will spread and the centers will look soft, but should look done. Remove just before the edges begin to turn golden. Don’t over bake. The cookies will be a little puffy when you take them out of the oven but will fall a bit as they cool.
10. Remove from the oven and allow to cool on baking sheets for 4-5 minutes before transferring to a wire rack to cool completely.
11. If you didn’t add the heart sprinkle prior to baking, melt the white chocolate and use a generous dot of white chocolate to attache the heart to the cookie. Allow to dry.