Baked shrimp with chili-garlic butter

1. *for milder flavor, seed some or all of the chilies.
2. De arbol chilies are usually sold in cellophane packages, along with other mexican food specialties.
3. They are a small, slender, almost needle-shaped chilie with smooth, bright red skin and a very hot flavor.
4. Preheat oven to 400°F.
5. Shell and devein shrimp, leaving tails attached; rinse and drain well.
6. Heat butter and oil in small skillet over medium heat until butter is melted and foamy.
7. Add garlic, chilies, lime juice and salt.
8. Cook and stir 1 minute.
9. Remove from heat.
10. Arrange shrimp in even layer in shallow 2-quart gratin pan or baking dish.
11. Pour hot butter mixture over shrimp.
12. Bakei shrimp 10 to 12 minutes until shrimp turn opaque, stirring once.
13. Do not overcook or shrimp will be dry and tough.
14. Garnishi if desired.