1. In a medium saucepan, saute the cilantro, garlic and jalapeno pepper in 2 tablespoons of butter or margarine over medium heat for 4 to 5 minutes. Add the stock, tequila and lime juice. Bring the mixture to a boil and cook until reduced to a paste-like consistency. Set aside.
2. Pour soy sauce over the chicken and set aside for 5 minutes. Meanwhile, In a medium sized skillet, saute the onion and the red, green and yellow bell peppers with the remaining tablespoon of butter or margarine, stirring occasionally.
3. Meanwhile, cook fettuccini according to package directions.
When the peppers have wilted, add the chicken and soy sauce. Toss and add the reserved tequila/lime paste and cream. Bring to a boil. Gently simmer until chicken is cooked through and sauce is thick. Toss with well drained fettuccini and garnish with cilantro. Serve.