Start by preparing the flavorful filling. Heat the cooking oil in a large wok or skillet over medium heat. Sauté the chopped onion and minced garlic until soft and fragrant, about 2 minutes. Add the cubed sweet potato and pour in the water. Allow it to boil, then drop in the Knorr Shrimp Cube. Cover the pan and simmer for about 5 minutes, letting the sweet potatoes absorb the savory flavor.
Once the water reduces, remove the lid and let the liquid evaporate. Stir in the fried tofu and shrimp, tossing everything together for about a minute. Add the cabbage, green beans, and carrot. Continue to stir-fry for another 3 minutes until the vegetables are slightly tender yet still crisp. Season with fish sauce and a dash of ground black pepper. Remove from heat and set aside to cool slightly.
Next, make the delicate lumpia wrappers. In a large mixing bowl, beat the eggs, then whisk in the canola oil and water until combined. Gradually add the all-purpose flour while whisking continuously until the batter becomes smooth and lump-free.
Preheat a non-stick pan over medium heat and lightly grease it with oil or spray. Pour about 7 to 8 tablespoons of the batter into the pan, swirling it around to create a thin, even layer. Cook for 1 minute or until the wrapper starts to pull away easily from the pan. Gently lift it out and place it on a plate. Repeat this process until all the batter is used up, stacking the wrappers neatly to prevent sticking.
Now, prepare the sweet and savory lumpia sauce. In a small saucepan, bring water to a gentle boil. Add the soy sauce, brown sugar, and minced garlic. Stir until the sugar dissolves completely. In a small bowl, dissolve the cornstarch in 3 tablespoons of water, then slowly pour it into the saucepan. Stir continuously until the sauce thickens and reaches a glossy consistency. Remove from heat and let cool slightly.
To assemble, place one wrapper flat on a large plate. Lay a Romaine lettuce leaf in the center, then spoon a generous amount of the fresh vegetable and tofu-shrimp filling over it. Sprinkle some chopped parsley for freshness. Fold the bottom of the wrapper upward to cover the filling, then tuck in both sides neatly, creating a snug roll. Repeat with the remaining wrappers and filling.
Arrange the finished lumpia on a serving plate. Generously drizzle each piece with the warm, thick sauce and sprinkle crushed peanuts on top for added crunch. Serve immediately and enjoy the harmony of crisp vegetables, savory filling, and sweet garlicky sauce in every bite