Boil (simmer) chicken with your choice of seasonings (such as: ginger, garlic, salt, pepper and soy sauce). Once cooked and cooled, shred chicken and place in a medium sized bowl.
Finely chop the water chestnuts and green onions. Add to the bowl with the chicken.
Add shredded cheddar cheese to bowl and mix well to combine all ingredients.
Prepare working area- with a shallow bowl of water, a cutting board or other surface for folding, and a tray or cookie sheet for lining up folded wontons.
Take a single wonton wrapper and dip a corner (half of the wonton) in water, then place on your work surface.
Pile a heaping teaspoon of the filling into the middle of the wonton wrapper, fold over carefully, and press the edges to seal. Place filled wonton on a tray or cookie sheet.
Repeat for all wontons.
In a shallow pot, or fry pan with tall sides, heat two inched of canola oil over medium-high heat. You know when your oil is hot enough when you drop a small piece of wonton in the oil and it instantly floats to the top, sizzling.
Fry wontons in hot oil, three or four at a time (don't crowd). Fry on one side for about 30-40 seconds or until the edges turn golden brown. Flip wontons over using tongs, and fry on flip side for another 20-30 seconds or so.
Remove wontons to a large plate or tray, lined with paper towels.
Serve hot, with soy sauce, if desired.