Begin by adding the oil to a medium pot, and warming on medium-high heat. During this time, take a few of the spring roll wrappers, and separate them. Beat the egg with the water.
Spread about 3 tablespoons of the mashed potato along the back edge of the spring roll wrapper. Add about 2 tbsp of the diced turkey, and begin to roll. Roll until you have 2 inches of the wrapper remaining. Brush with egg wash, fold over the sides, and continue to roll, sealing the egg roll. Repeat with however many egg rolls you want to make.
Add the egg rolls into the hot oil, making sure they are tightly sealed. Cook for about 3 minutes, then using tongs, spin them a bit, making sure you cook the other side. Remove them from the oil, and let the drain on a lined strainer with paper towel. Repeat with any remaining egg rolls.
As they drain any access oil, warm up your gravy in a pot on the stove top, or in a microwave, until it is nice and hot. Stir well.
Slice the egg roll on a diagonal, and serve with the gravy.
When I bit into these, I was blow away. Dipping them into the gravy was on a whole other level, and this made for probably one of the best Thanksgiving leftover dishes I have ever made. Other ideas is to toss in some dressing, or stuffing to pick it up another level. My attempt at trying one with the cranberry sauce, failed, as the wrapper did not want to hold the sauce itself. Regardless, you can get as creative as you want. The intent is to enjoy, and turn on the family the next day. This one is sure to please.