Cook the pasta in hot water for 3-5 minutes, drain, rinse with cold water, cut shorter with scissors and drain. Wash the meat, dab dry and cut into slices. Peel and chop onion.
Heat the oil in a pan and fry the meat all around. Season with salt and pepper and remove. Put the vegetable mixture and onion into the hot pan and fry for about 1 minute over a high heat.
Then cook over medium heat for 9-11 minutes. Stir several times in between. Remove from heat. Add meat and chili sauce. Mix in the noodles and season with lemon juice and salt if necessary. Serve while still warm.