Heat oil in a deep non-stick wok and saute onions and garlic, till lightly browned and fragrant. Add in tofu and fry for a few minutes till crisp around the edges. By this time, the onions and garlic should be caramelized and very fragrant.
Add in the shredded cabbage and Sambal Olek, and stir-fry for a few minutes to combine well. Stir in noodles, sprinkle soya sauce, and stir fry to coat noodles well with the sauce and veggies. Season with salt and serve warm.