If you're preparing your own egg roll wrapper dough, fill a medium-sized basin with flour and salt. After a little mixing, make a well.
After cracking the egg into the well, stir the mixture with a fork, being sure to include the well's sides. One spoonful at a time, gradually add the warm water, mixing in an increasing amount of dough.
Continue until the dough starts to get shaggy. Take the dough out of the bowl, transfer it to a floured surface, and knead it for two to three minutes, or until a smooth, slightly sticky dough forms. To make the dough less sticky, add flour. If dough isn't sticking together and is too dry, add a little extra water.
Divide dough into four equal pieces. Put the dough you won't be spreading out aside after wrapping it in plastic wrap.
Roll out the dough as thinly as possible using a rolling pin on a large floured cutting board or counter. To avoid sticking, dust the rolling pin and surface with flour as needed. After rolling out to a large thin disk, carefully place it on parchment paper. Cut long strips that are 1/4 to 1/2 inch broad with a knife or pastry wheel. Then, cut crosswise to create strips that are 2-3 inches long. Put away the parchment paper.
Proceed with the remaining dough. Alternately, create as much as you like and save the remaining dough for a future use by storing it in the refrigerator or freezer.
Simply cut the pre-made egg roll wrappers into strips that are 2-3 inches by 1/4 to 1/2 inch if you're using them.
To verify if the oil is ready, use the wooden spoon test or add 3–4 inches of vegetable or peanut oil to a skillet and heat over medium heat until the oil reaches 375°F (see recipe notes).
Dredge dough strips in oil, frying for 30 to 60 seconds, then flipping and frying for an additional 30 to 60 seconds, or until golden brown. Removing with a slotted spoon, allow it drain on a dish covered with paper towels. Continue doing this with all of the dough strips.
Pour soup into dish, add chopped green onion and crispy egg roll wrapper strips on top, and serve!