Birthday SMASH

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Birthday parties just got an upgrade with these Birthday SMASH cookies. Part vanilla, part chocolate, and ALL tasty that you really can’t lose with this one.

This cookie is for all you cookie lovers who prefer a cookie birthday celebration over a cake. No dis on a cake, but I will always take a cookie over a cake. The tricky party has always been trying to decide It seemed unfair that cakes hard a marble version but such limited options for cookies. Luckily I feel this cookie helps open up the door for us cookie lovers and I hope you feel the same once you’ve given it a try!

Cookie 411

Difficulty: This cookie is probably the EASIEST cookie out of the entire bunch. One bowl, ingredients that you just throw in and VIOLA – instant deliciousness. Rating on this one is a solid 1 out of 10 (1 easy, 10 difficult).

Flavor: ahh I thought you’d never ask! Vanilla base is combined with white chocolate chips and rainbow jimmies, while the chocolate base has dutch cocoa with semi-sweet chocolate morsels and chocolate sprinkles. Swirl those together AND THEN top with rainbow nonpareils. *chefs kiss*

Shelf Life: pack these babies up in a ziplock bag to stay fresh for up to 5 days without refrigeration. You can also freeze in freezer safe ziplocks bags/reusable bags for up to 3 months. Midnight snack here I come.

EXTRA EXTRA: Obviously this cookie is meant to be a replacement for the birthday cake, so naturally I went extra on it and topped it with chocolate ganache. Totally optional but is it? Birthdays are for celebrating, so do yourself a favor and top that bad boy with some chocolate.

Tips & Tricks

Half & Half: So this recipe allows you to break down the flavors of vanilla and chocolate how you wish. I opted for a ? vanilla and ? chocolate because I found the chocolate to be overpowering the vanilla flavors. But if you love yourself chocolate more than vanilla than definitely flip that script.

Sprinkles: Birthdays should be fun and joyful, and how else can we make that happen in a cookie than with sprinkles? I use rainbow and chocolate jimmies (the little rodlike ones) WITHIN the dough. The rainbow nonpareils (rainbow balls) I TOPPED the cookie with. But hey, you do you.

WAIT FOR IT: I am a firm believer in chilling your cookie dough for a minimum of 12 hours and up to 24 hours, although I 90% of the time wait the 24 hours. Why? Because it allows the flavors to truly seep into that dough and explode in your mouth once baked.

Feeling Fancy?: Me too, which is why I topped this cookie with a chocolate ganache frosting. You can also top with chocolate buttercream, vanilla buttercream, dunk in melted chocolate ganache, etc. It’s truly up to you! Just don’t forget those birthday sprinkles and candle.

Tools For The Job

kitchen scale

silicone baking mat

3 tbsp ice cream scoop


rubber spatula

fine mesh strainer

Birthday SMASH Cookies

Yields: 12 cookies

Prep Time: approx. 30 minutes

Chill Time: minimum 12 hours or up to 24 hours

Bake Time: 13 – 14 minutes

Total Hands On Time: approx. 1 hour


325 g (2 ½ cups) all purpose flour

220 g (1 cup, 2 sticks) unsalted butter, melted

100 g (½ cup) sugar

50 g (¼ cup) light brown sugar, packed

1 large egg PLUS 1 egg white, room temperature

2 tsp vanilla extract

1 tbsp cocoa powder

1 tbsp corn starch

¼ tsp baking soda

¼ tsp baking powder

½ tsp fine sea salt

4 tbsp rainbow jimmies

4 tbsp white chocolate morsels

3 tbsp chocolate jimmies

3 tbsp semi-sweet chocolate morsels

rainbow nonpareils for topping


In a large bowl, microwave butter for 20 – 25 seconds until almost completely melted. Using a whisk, whisk butter to incorporate parts of butter that did not fully melt. Add sugars and vanilla, and whisk until well combined. Add egg and egg white and whisk until well combined – about 1 to 2 minutes. In a separate bowl, combine flour, corn starch, baking soda, baking powder and fine seal salt and mix until thoroughly mixed. Add dry ingredients mixture to wet ingredients, and whisk until all the flour is fully incorporated.

Place ? of the dough into a separate bowl. Sift in the cocoa powder with the fine mesh strainer, and then use a rubber spatula to incorporate the cocoa powder into the dough. Mix well and thoroughly to ensure it is evenly distributed. Add semi-sweet chocolate morsels and chocolate sprinkles, and fold in until evenly distributed.

With the other ? vanilla dough, add in white chocolate morsels and rainbow jimmies and fold in well until evenly distributed. Move vanilla dough to cover one side of the bowl it currently resides in leaving the other half of the bowl open so that we can place the chocolate dough on that end. Place the chocolate dough right next to the vanilla dough. Taking the 3 tbsp ice cream scoop, begin on one end of the bowl and finish scooping towards the other end (begin with vanilla and scoop towards chocolate, or vice versa). There is no right or wrong way, just make sure you are pulling in both flavors as you scoop.

Place dough on baking sheet lined with a silicone baking mat, and place dough balls at least 2” apart. Top with rainbow nonpareils if desired. Place in refrigerator for a minimum of 12 hours or up to 24 hours.

Preheat oven to 350 F. Remove cookies from fridge and place directly into oven once preheated. Bake for 15 minutes, or until you begin see bottom edges browning. Remove from oven and place on wire rack to cool. You can top with chocolate ganache, chocolate frosting, vanilla frosting, etc if you’d like, or enjoy as is.

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