Pour vegetable oil into a large deep skillet and heat on a large burner. You want the oil to get to 375 degrees.
While the oil is heating up, use a bottle cap or small round cookie cutter to cut a whole in the middle of the dough. Repeat this process until all the dough is cut.
Once the oil is heated add donuts 2-3 at a time to the pan. Fry for 30 seconds then flip and fry on the other side for 20-30 seconds. Carefully remove from oil using a slotted spoon and place on paper towels. Repeat until all donuts are fried.
Heat dark chocolate in the microwave in 20 second increments until melted. When donuts are cooled dip the donut top down into the bowl (a shallow one works best) of chocolate and remove and set aside. Repeat until all donuts are coated with chocolate. Add sprinkles if desired and enjoy!
*You want the oil to be at least an inch deep. Depending on the pan you use you may need more or less than the recipe suggests.Leftover Storage: Store leftovers at room temperature for up to 4 days.Freezer Option: Store leftover donuts in a freezer bag for up to 2 months. Re-warm in the microwave until de-thawed.