Prepare the shrimp by snipping the shell down the back with a pair of kitchen scissors. Remove veil. Traditionally, the shells are left on, but I prefer to remove them.
In a large bowl, combine ale, broth, melted butter, oil, garlic, Worcestershire sauce, rosemary, salt, pepper, paprika, thyme, cayenne, granulated onion, and white pepper. Add shrimp to mixture. Gently toss to coat. Cover with plastic wrap and place in the refrigerator for 30-40 minutes.
Preheat your grill for medium-high heat. Place a cast-iron skillet on the grill and heat it up for about 10 minutes; until it’s good and hot.
Add the shrimp marinade into the pan first. This will become the sauce. Let it bubble up and cook for about 3 minutes. Stir through and watch for burning.
Now, add the shrimp and cook for another 5 minutes, turning often.
One shrimp are cooked through, firm and pink in appearance, and the sauce has simmered and reduced a bit, remove the cast iron pan from grill.
Carefully place contents into a serving dish, or carefully set the pan on a sturdy hot pad. Serve with rice or a good crusty bread, and dig in!