Combine all ingredients (except the last 3 ingredients) in a large bowl and mix thoroughly. Place cornstarch (or flour) in a small bowl. Add enough water until the consistency is slightly thicker than milk. You’ll need this to seal the edges together.
Lay one piece of wrapper on a clean, flat surface. Fill the large Ziploc bag with the lumpia mixture and push it to one corner of the bag. Snip a small hole and squeeze the bag. Pipe a thin layer near the end of the wrapper nearest you (leave ½ inch border at the bottom so it’s easier to roll). Roll halfway, brush the opposite end with your edible “glue” and roll until fully sealed (both ends will be open.) Alternatively, add a little over 2 tablespoons of mixture to the center of the wrapper and spread evenly. Roll and seal the ends. Repeat until everything’s wrapped.
Using kitchen scissors, divide each roll into desired lengths. (See instructions above if freezing)
Fill a large (and slightly deep) frying pan with 1 inch of oil. Heat oil and fry lumpia until golden. Do not crowd the pan (temperature will drop) or your rolls will be oily. Turn the rolls occasionally for even cooking.
Place the rolls (preferably upright) in a paper towel-lined colander to drain excess oil. Then transfer to your desired serving dish. Serve with sweet chili sauce or ketchup for dipping,