Prepare the dough:

In a mixing bowl, combine flour and salt. Slowly pour in boiling water while stirring with a spoon. Add the vegetable oil, then knead until smooth and elastic. Cover and let rest for 30 minutes.

Optional filling prep:

If using a filling, heat 1 tbsp oil in a pan. Add onion and garlic, sauté until translucent. Add cabbage, carrots, soy sauce, salt, and pepper. Cook until soft. Let cool.

Roll out the dough:

Divide the dough into equal portions. Roll each into a thin rectangle or circle.

Fill and roll:

Place a spoonful of the cooled filling in the center of each piece of dough. Fold and roll tightly like a spring roll.

Heat the oil:

Pour enough oil into a frying pan to deep-fry. Heat over medium-high heat.

Fry the rolls:

Fry the rolls in batches until golden brown and crispy (about 3–4 minutes per side). Drain on paper towels.

Serve hot:

Enjoy crispy vegetable rolls as a snack, side, or appetizer.