1. Prepare the batter: In a pot place water, margarine, salt, and sugar, and heat until the margarine is melted. Stir in 3/4 cups of flour and continue stirring with the flame on until the batter pulls from the side of the pot and leaves a trail. Transfer to another high-sided pot or bowl and add, one at a time, four eggs, making sure each egg is fully incorporated before add the next. Set the batter aside.
2. Grate the potato and sweet potato. Squeeze out the excess water from the regular potatoes. Add the shredded potatoes, one tablespoon onion flakes, chives, tarragon and one teaspoon salt and pepper to the choux paste batter. Stir together and set aside.
3. Fill a medium sized pot with three inches of oil and heat to 350 degrees. Using a one-ounce ice cream scoop or table spoon drop four to five balls of batter into the oil. Fry for four to five minutes or until nicely browned. Do not overcrowd the fryer. Once done set aside on a paper-towel-lined plate and fry the next batch.
4. Serve with sour cream or applesauce.