Cut beancurd (tauhu) pieces diagonally into halves. Sprinkle a little salt. Pat dry with paper kitchen towels, then deep-fry in hot oil until crispy on the outside.
Cut a slit in the tauhu and pry open slightly. Stuff with a little bit of each vegetable into the opening.
For the sauce: heat two tablespoons oil in a wok and saute the combined pounded ingredients until fragrant. Add asam jawa juice and seasoning. Bring to a simmering boil until sauce turns thick. Dish out and serve with the tauhu sumbat.