Combine cocoa, flour, sugar, baking powder, baking soda and salt in a large mixing bowl with a wooden spoon.
In a separate bowl, whisk eggs, half-and-half, sour cream, chocolate extract and melted butter.
Place Oreos in a zip lock bag WITHOUT the "stand and fill" bottom and crush with a rolling pin; set aside.
Combine dry mixture with wet mixture and crushed Oreos, just until mixed.
Do not over-mix the batter.
This is a very thick batter.
Spoon mixture into another Ziplock bag (WITHOUT the "stand and fill" bottom") and cut off the corner.
Pipe the donut mixture into greased donut pans.
Bake at 350 degrees for about 8-10 minutes.
Check with a toothpick for doneness.
Do not over-bake or donuts will become tough.
Remove from oven.
Cool in donut pan about 5 minutes before removing to wire racks to ice donuts.