Boil rice noodles until al dente, drain, toss with 1 tsp oil, and cool.
Heat vegetable oil in a wok on high flame until smoking.
Add garlic paste and red chili powder paste mixed with 1 tbsp water; sauté for 30 seconds.
Add sliced capsicum and cabbage; stir-fry rapidly for 2 minutes.
Toss in noodles, soy sauce, vinegar, black pepper, and salt continuously for 2 minutes before serving hot.