Salt, to taste Prepare pasta according to package directions; drain. Warm the margarine in a large saucepan over medium-low heat. Add the onion and saute until lightly brown and very soft. Add the flour and reduce heat to low. Stir until completely blended. Very gradually whisk in the white wine and chicken broth. Bring the sauce to a boil and then let simmer for 10 minutes. Stir in the lemon zest, thyme, dill and mustard and season to taste with salt. Serve sauce over the warm pasta. Calories per serving........... 302 Fat.................. 7.41 g Cholesterol.................... 0 mg Sodium............... 417 mg