1 tbsp. olive oil
1 lg. yellow onion, chopped
1 clove garlic, minced
1 med. carrot, peeled and finely chopped
1 med. celery stalk, chopped fine
1 sm. sweet red pepper, cored, seeded and chopped fine
1/2 tsp. each dried basil, marjoram and rosemary, crumbled
1/4 tsp. black pepper
1/2 c. dry white wine
2 tbsp. flour
1 3/4 c. low-sodium chicken broth
6 oz. med. pasta shells
1 (6 1/2 oz.) can water packed light tuna, drained and flaked
3 tbsp. Parmesan cheese
1 tbsp. lemon juice
1/4 c. minced parsley

1. Heat the olive oil in a heavy 12 inch skillet over moderate heat for 1 minute. Add the onion, garlic, carrot, celery, red pepper, basil, marjoram, rosemary and black pepper. Cook, uncovered, stirring occasionally, until the vegetables are soft - 5 to 8 minutes.

2. Add the wine to the skillet and boil, uncovered, for 3 minutes. Place the flour in a small bowl and add enough of the chicken broth, a tablespoon at a time, to make a smooth paste. Blend in the rest of the chicken broth and add to the skillet. Cook, stirring constantly, until slightly thickened - about 3 minutes. Lower the heat so that the mixture bubbles gently, cover, and simmer for 8 minutes or until the sauce has thickened.

3. Meanwhile, preheat the oven to 350 degrees. Cook the pasta shells according to package directions, omitting the salt. Drain well and place in an ungreased 2 1/2 quart casserole. Add the tuna but do not mix.