Peel and clean the cucumber, cut it in half lengthwise, remove the seeds and cut into strips. Peel and wash carrots and cut them into very thin slices. Wash the meat, dab dry and cut into strips.
Cook the pasta in boiling salted water according to the instructions on the packet. Heat the oil in a frying pan. Sauté the meat for about 6 minutes while turning, after 4 minutes add carrots and cucumbers. Dust with flour and sauté briefly.
Add the stock and milk while stirring. Bring to the boil and simmer for 2-3 minutes. Stir in mustard and season to taste with salt and pepper. Meanwhile wash parsley, shake dry, pluck leaves from the stalks and cut into strips, except for a little garnish.
Arrange noodles and ragout on plates and sprinkle with parsley.