Crush Oreo cookies; set aside.
Mix flour, soda, salt in bowl; set aside.
Melt butter in a saucepan over medium. (It will begin to foam - continue stirring)
Butter will start to brown and give off a nutty smell.
Transfer butter (immediately) to a glass bowl to prevent burning.
Set aside; let cool for a few minutes.
In a mixer, combine butter and sugars.
Beat in egg, yolk, vanilla, and yogurt.
Slowly add dry ingredients - beat on low.
Gently fold in crushed Oreos.
Roll into 1 1/2 TB balls. (use the purple #40 ice cream scoop)
Chill for several hours or overnight.
Bake 12 cookies per sheet at 350 for 9 minutes.
Use a small cup to shape the hot cookies as soon as they are out of the oven.