1. Melt 1/2 cup butter in a large skillet over medium heat.
2. Add onion, green chilies, bell pepper, 1 tsp salt, 1 tsp white pepper 1/2 tsp cayenne, 1/4 tsp oregano and garlic.
3. Saute 10 minutes, stirring often.
4. Stir in cream.
5. Bring mixture to a boil.
6. Reduce heat& simmer for 10 minutes, stirring constantly.
7. Add sour cream, whisking until well blended.
8. Add cheese, stirring until well blended.
9. Set aside.
10. Melt remaining 1/2 cup butter in a 4 quart saucepan over medium heat.
11. Add crawfish, green onion, remaining salt, pepper, cayenne and oregano.
12. Saute for 6 minutes, stirring occasionally.
13. Add cheese sauce stirring until well blended.
14. Simmer for 6 to 10 minutes stirring occasionally.
15. Serve with tortilla chips or your favorite cracker.