Rinse the guinea-fowl brests, dry them gently and slice them in strips. Clean the asparagus removing the tougher part, peel them with a potato peeler, rinse them and chop them into chunks. Peel the carrot and the onion, clean the celery removing the white parts, and, once washed, finely chop the whole lot of vegetables.Blanch the tomatoes in boiling water, peel them, deseed them and remove the cooking water, then chop them coarsely. Rinse the thyme, dry it and slice it. Put the oil and the butter in a saucepan add the vegetables and fry until soft but not golden. Add the strips of guinea-fowl and golden; sprinkle with white wine and let it evaporate over a medium heat.Add the chopped tomatoes and 1/2 glass of water, salt, ad a pinch of salt and a grind of pepper and simmer over a medium heat for 30/40 minutes, stirring with a wooden spoon. In the meanwhile steam the chunks of asparagus for 7/8 minutes, drain them and add them to the guinea-fowl ragù five minutes before they are ready.Cook the pasta in a saucepan with plenty of boiling salted water. Drain it al dente and. Dress with the guinea-fowl and asparagus ragù, sprinkle with thyme and serve immediately.