Preheat oven to 350F degrees.
If you're using whole milk instead of buttermilk. In a small bowl, pour in 3/4 cup whole milk and 1 tsp vinegar (I used apple cider). Let stand for about 5 minutes until it starts to look curdled.
In a large mixing bowl or stand mixer, cream together the butter and sugars until light and fluffy. Add in the egg and vanilla extract and mix until combined.
Next, add in the flour, sea salt, baking powder and baking soda and mix until well combined.
Slowly pour in the buttermilk or whole milk mixture and mix while adding it in until the dough is soft.
Fold in 2/3 cup of sprinkles with a spatula very gently until just incorporated.
The batter will be very soft so the best thing to do here is refrigerate the dough for 30 minutes to harden up first.
When you’re ready, scoop dough onto a lined baking sheet (either parchment paper or a silpat). I love using a cookie scooper because I find it easier to use. You can also just scoop out with a big spoon. Make sure to give them space because they will spread a good amount.
I made 16 cookies this time around. You can make yours larger or smaller! Just adjust your cook time.
Bake for 10-12 minutes. You want the tops set but soft. They’ll continue to cook when you take them out so don’t over bake!
Once done, cool on the baking sheet for about 5-10 minutes and then move to a wire rack to cool completely.