In a saucepan, melt the butter over medium heat. Continue cooking as it bubbles and splutters. A foam will develop on top. Once it goes silent and the foam disappears, you’ll see some brown bits at the bottom and smell a nuttiness, this means it’s done.
Remove from heat immediately once browned, and place in a heat-safe bowl. Make sure you have 135g browned butter. Add salt and stir. Place bowl in the fridge, allow to firm up for about an hour (when it’s time to make the dough, consistency should be thick like softened butter and color will be white on top with brown bits settling at the bottom)
Preheat oven to 350.
Cream browned butter and sugars for 5 minutes until mix is very light in color.
Add egg yolks, cream for another minute. Make sure to keep scraping your bowl for unmixed bits.
Add yogurt, vanilla, baking soda. Beat to combine.
Add flour, mix just to combine.
Fold chopped chocolate into dough.
Portion into about 2 tablespoons, roll gently in sprinkles or sprinkle on flaked sea salt.
Bake for 10 minutes.