Melt the butter in a heavy bottom sauce pot.

Whisk in the flour and cook until a medium dark brown roux is achieved.

Add the onion, bell pepper, celery, garlic, salt and black pepper. Cook until the onions are translucent.

Slowly add the shrimp stock. Whisk out any lumps. Bring to a full boil then reduce heat to a simmer. Cook until thick enough to heavily coat the back of a spoon.

Serve 2 cups of the sauce over cooked grits.