Beat cream cheese with an electric mixer on low in a bowl until slightly fluffy. Add peach, confectioners' sugar, and vanilla extract; beat until mixed. Cover bowl with plastic wrap and refrigerate to chill slightly, about 10 minutes.
Heat vegetable oil in a deep-fryer or large saucepan to 350 degrees F (175 degrees C).
Place a wonton wrapper on a work surface; spoon about 1 tablespoon cream cheese mixture into the center. Pour water into a small bowl, dip your finger in the water, and swipe all 4 sides of the wrapper. Fold one corner of the wrapper over the filling, forming a triangle shape. Press the edges of the wrapper down to seal all the sides. Repeat with remaining wrappers and filling.
Fry 4 to 5 wontons at a time in the hot oil until lightly browned, about 3 minutes per side. Remove with a slotted spoon; drain on a paper towel-lined plate. Repeat with remaining wontons.
We have determined the nutritional value of oil for frying based on a retention value of 10% after cooking. The exact amount will vary depending on cooking time and temperature, ingredient density, and the specific type of oil used.