this is a classic sprinkle cookie, no big surprises. you can go two routes with the mixing:

① traditional creaming 
② melted butter

both methods will produce a great result, but ① requires a stand mixer and ② does not. method ① will make a fluffier cookie thanks to the additional air incorporated when creaming the butter and sugar. method ② will make a chewier, flatter cookie, which i favor. it’s also much quicker than creaming, which i am never mad about.

notes: it’s ’s a great idea to melt the butter first and set it aside while you measure all of the other ingredients, allowing time to cool. i’ve provided the ingredients in gram measurements because sometimes with baking, the difference between a good or bad cookie can be dependent on how a “cup” of flour or sugar is scooped. for this reason i’ve provided the recipe in grams as well as cup measurements. i advise going by grams whenever possible!

ingredients

makes 10-12 big cookies

2 sticks butter, unsalted (228g)
1 cup granulated sugar (200g)
1/2 teaspoon salt (3g)
2 egg yolks (40g)
1 tablespoon milk (15g)
1 teaspoon vanilla (4g)
2 cups all purpose flour (240g)
1 teaspoon baking soda, sifted (3g)
3/4 cup rainbow sprinkles (120g) 
+3 tbsp granulated sugar, for dipping 

method

follow one of the mixing methods below:

① traditional creaming method:
combine softened butter, sugar, and salt in a stand mixer. mix on low-medium to bring together, then raise to medium and beat until pale and fluffy, about 3 to 5 minutes. stop mixing, scrape down the bowl, then add the yolks, milk, and vanilla and mix to incorporate. add flour, baking soda, and sprinkles to the mixing bowl all at once. mix on low speed just until the flour is incorporated and there are no dry streaks (check/scrape the bottom of the bowl). 

② melted butter method:
in a small pot, heat butter over low-medium heatuntil most of it is melted. remove from heat and allow the residual warmth to melt the remaining butter. allow to cool to room temp. in a large bowl, whisk together cooled butter, sugar, and salt, followed by the yolks, vanilla, and milk. add flour, baking soda, and sprinkles to the mixing bowl all at once and fold in gently with a spatula until the flour is incorporated and there are no remaining dry streaks (check/scrape the bottom of the bowl).

to bake:
preheat oven to 350º F and line a baking sheet with parchment. scoop cookies with a 1.6oz yellow scoop (about 3 tablespoons of dough per cookie). dip each dough ball in sugar, then place on baking sheet with enough room for each to spread out (i bake 6 on a half sheet). bake for 7 minutes, then carefully remove from the oven and smack the pan on the counter (lined with a kitchen towel). return to the oven and bake another 5-6 minutes, or until lightly golden brown around the edges and cracked on the surface.

note: if you are making this dough in advance, bring it back to room temp before baking or they won’t spread properly.