Heat butter and oil in a large saucepan on medium heat.
Add potatoes, onion, celery, bell pepper, Old Bay Seasoning and bay leaf.
Cook and stir 8 minutes or until potatoes are tender
Sprinkle with flour
Cook 2 minutes, stirring constantly.
Stir in milk and chicken broth.
Bring to boil.
Add corn and crabmeat.
Reduce heat to low and simmer 5 minutes.
Remove & discard bay leaf