In a large pot or stock pot, heat butter and oil over medium heat. Add the onions and celery and cook until soft and transparent but not browned, about 5 minutes.
Stir in the flour, making a roux, then add the broth and the clam nectar. Add the potatoes, carrots, thyme, bay leaf and paprika. Reduce heat to medium, cover, and cook for 15 minutes or until potatoes are tender but not mushy.
Add the seafood, wine and seasonings, stir gently and cook uncovered for about 10 minutes.
Gently stir in the cream, being careful not to let to boil after this is added. Remove the bay leaf.
Garnish with more fresh dill and serve hot.
Carrots are optional. Some people like them in a seafood chowder, some don't!