In a heavy dutch oven or heavy bottom pot, add 3-4 inches of vegetable oil for frying. It is best to use a candy thermometer to make sure the temperature is what you want. Bring to 375 ºF. Add pancake mix, milk, vegetable oil and egg to a mixing bowl.
Whisk until most of the lumps are gone. The mixture should be thick enough to coat your oreo without the batter running off. Add more mix if the batter is too thin. Let batter sit for 5 minutes.
Immerse an oreo into the pancake batter with your hands. Coat completely. Allow excess batter to drip off. Carefully put oreo into the hot oil. Flip occasionally with a slotted utensil to get an even deep golden brown on both sides of the oreo.
Remove golden oreo from the oil. Place on a wire rack covered in paper towel to absorb excess oil. Repeat with the rest of the oreos.
Allow to cool for 5-10 minutes. Serve