Heat butter and oil in a large, heavy skillet over medium-high heat.
Add the onion, reduce heat to medium-low and cook 3 to 4 minutes or until beginning to soften.
Add the green bell pepper and celery. Cook 7 to 8 minutes or until very soft.
Stir in garlic, flour, Cajun seasoning and cayenne and cook briefly (15 seconds).
Add sausage, chicken broth and tomatoes. Bring to a boil, reduce heat to low and simmer for 8 to 10 minutes or until reduced slightly and thickened.
Stir in shrimp and cook 2 to 3 minutes or until just firm.
Stir in heavy cream and heat through. Stir in parsley. Serve with grits.
Bring chicken broth to a boil. Add salt to taste.
Slowly stir in quick grits and cook per package directions.
Stir in cheese, cream and black pepper. Serve with shrimp.
