In a large bowl, combine the onion, carrots, scallions, garlic, cabbage, 1 egg, 1 egg yolk, salt, and pepper until well blended. Add the beef and pork and mix with your hands until is evenly distributed.

In a small bowl, whisk a splash of water into the remaining egg white. Working one at a time, on a work surface, place a lumpia wrapper with 1 corner facing you. Place 1 heaping tablespoon of the filling in the center of the wrapper and shape into a thin horizontal 5-inch-long log. Dip your fingers in the remaining egg white mixture and lightly brush the edges of the wrapper. Roll the bottom corner up and snugly over the filling, then tuck under the filling. Fold the left and right corners tightly over the filling to enclose. Crease the wrapper with your fingers, then continue to roll the bundle away from you. Both sides should be as close to sealed as possible; use a little egg wash to seal, as necessary.

In a large nonstick pan, fill with oil to a depth of 1 inch. It should cover the lumpia at least halfway when frying; adjust the amount if needed. Heat the pan over medium-high heat. You’ll know the oil is hot enough if you place the tip of lumpia into the oil and it bubbles immediately. Cook the lumpia for 2 to 3 minutes per side, until deep golden brown and crisp. Transfer to a paper towel-lined wire rack. You can serve whole or cut in half. Serve with the sauce alongside.

In a small bowl, mix the vinegar, soy sauce, garlic, chile, and scallion. Decant into a small dish.