Peel onions and garlic. Cut onions into strips, garlic into pieces. Clean, wash and cut the chilli pepper into rings, removing the white seeds. Wash the meat, dab dry, halve lengthwise and cut into slices.
Prepare the pasta in boiling salted water according to the instructions on the packet. Heat the oil in a large pan. Fry the meat for 2-3 minutes while turning. Add chilli, garlic and onion and fry briefly.
Season with salt and pepper, dust with flour and sauté briefly. Add tomatoes and stock while stirring. Bring to the boil, simmer for about 5 minutes. Wash basil, dab dry, except for something to garnish, pluck leaves from the stalks and chop finely.
Season the shredded meat with salt, pepper, vinegar and a little sugar. Stir in basil. Drain the pasta and let it drain. Serve the shredded pasta on plates and garnish with basil.