1. Prepare the pesto sauce. In a mortar crush the garlic with salt to form a paste. In a food processor or a mortar blend the garlic paste with basil, walnuts and olive oil and purée. Add the cheese and set aside.
2. In a heavy skillet heat the vegetal oil and sauté the chicken, turning once; cook 10 minutes. Remove from the heat and cut the chicken in small pieces.
3. In a large saucepan with plenty of boiling salted water cook the pasta al dente. Strain the pasta and return to the pan. Add the pesto sauce and chicken. Mix well, correct seasonings and serve immediately.