Mix together the bisquick and whole milk in a bowl. Set aside.
Heat the oil in a deep fryer (or large, heavy-bottomed pot) to 375˚F.
Working in batches, coat the Oreos in the batter and carefully add to the hot oil. Fry for about 2 minutes, flipping halfway through until the batter is golden brown.
Drain on a paper towel lined plate. Sprinkle with powdered sugar.
Video
Notes
Nutrition facts were calculated using three tablespoons of oil since most of it wasn't absorbed. Your results may vary depending on your oil temperature, length of cooking time, and the fryer you use.