Preheat the oven to 375°F. Line a large baking sheet with parchment paper and set aside.

Combine cake mix, butter, and eggs using a hand-held or stand mixer until just combined.

Add vanilla extract and green gel food coloring, mixing until the desired green color is met and fully blended.

Chill the dough for at least 30 minutes before baking.

Whisk together powdered sugar and cornstarch in a small mixing bowl.

Scoop out the cookie dough with a 1 1/2 tablespoon cookie scoop, rolling gently in hands to shape.

Coat the dough balls in the powdered sugar mixture.

Place the cookies onto the lined baking sheet, pressing down slightly, and bake for 10-12 minutes, or until the cookie edges start to brown a little bit.

Remove the cookies from the oven and gently place one heart-shaped sprinkle onto each cookie.

Allow the cookies to cool for 5-10 minutes before moving them to a wire rack to cool completely.