Bring water for pasta to a boil. Meanwhile, bring milk, broth, garlic, bay leaf, thyme and pepper to a boil. Remove from heat. Cover and let stand for 15 minutes. Remove bay leaf.
Melt margarine in saucepan. Stir in flour; cook, stirring constantly, until mixture is bubbly; about 1 minute. Add milk mixture, whisking constantly. Remove from heat. Cover and let stand for 2 minutes.
Return pan to medium high heat and bring to a boil, whisking constantly. Reduce heat to medium low. Simmer, stirring often, until sauce has thickened and is smooth, about 8 to 10 minutes. (I added a bit of Wondra flour to this to thicken it a bit more, but be careful not to get it too thick.) While sauce is simmering, cook pasta in boiling water; drain.
Microwave vegetables until just tender. Chop into small pieces.
Add tuna and vegetables to sauce and mix. Carefully fold in cooked pasta. Posted in KitMail by MRSBOWLER@aol.com.