Peel and wash the carrots. Then cut them in half crosswise, first into thin slices, then into thin strips. Peel and wash celery and cut into thin strips. Clean the mushrooms and remove the stalks.
Cut the mushrooms into thin slices. Cut the leek lengthwise to the middle, wash and cut into thin strips. Heat 1 tablespoon of oil in a frying pan. Add celery and carrots and sweat for 2-3 minutes.
Add mushrooms and leek and season with some soy sauce, pepper and Sambal Oelek. Remove the vegetables from the pan after 3-4 minutes. Place 6 spring roll leaves side by side on the work surface. Place 1-2 tbsp. of filling on the bottom, leaving 2 cm of edge free at the edge.
Brush the edges with water and first fold the sides over the filling, then roll up firmly. Proceed in the same way with the remaining pastry sheets. Heat the oil in a saucepan and bake the spring rolls in portions in hot oil for 2-4 minutes until golden brown.
Asian chili sauce tastes good with it.