Preheat oven to 350°F and prep pan with non-stick baking spray.
Using a standing mixer, cream butter and sugar until smooth and fluffy.
Mix in the egg and vanilla.
In a separate mixing bowl, whisk together dry ingredients.
Slowly mix dry ingredients into bowl of wet ingredients.
Fold in the chocolate chips, chocolate chunks and M&Ms by hand with a wooden spoon.
Press batter into the heart shaped pan.
Add pink and white heart sprinkles to top of cookie.
Bake at 350 for 20-25 minutes or until lightly browned on the sides.
Remove from oven and allow to cool completely before frosting.
For the Frosting:
Using a standing mixer to beat together all frosting ingredients (minus food coloring) until smooth and stiff peaks form.
Mix in a few drops of the pink coloring until you have a nice rich pink color.
Scoop frosting into piping bag fitted with a star tip.
To Decorate:
Pipe frosting along the edge of the cookie cake and finish with more sprinkles.
Feel free to use a fine tip in your decorating bag and write a Valentine message on the middle of the cookie in frosting!
Video
Notes
Note: Nutrition information is a rough estimate only; actual values will vary based on the exact ingredients used and amount of recipe prepared.Frosting: This makes a big batch of frosting, and you'll likely only use half to decorate the cookie. We based our nutrition calculations on half a batch of frosting.
Gluten Free Instructions:
To start, simply swap out the regular all-purpose flour for gluten free flour. I recommend choosing an all-purpose gluten free flour for the task. You may also want to check the packaging on the rest ingredients you're using to make sure they are processed in a gluten-free facility, if cross-contamination is of concern.