Shrimp Boil in the Oven

Start the Shrimp Boil:
1 Preheat the oven to 450°F.
2 Poke holes in the potatoes with a knife (to prevent them from exploding!). Place them in a large bowl and microwave for 7-10 minutes, tossing every few minutes, until a fork easily pierces through.
3 In a 15-inch cast iron skillet (or two 9x13-inch baking dishes), combine the potatoes, sausage, and onion. Drizzle with olive oil, season with salt, and toss to coat.
4 Bake for 15 minutes.
6 Remove from the oven and add the corn to the skillet. Return to the oven and bake for 10 more minutes.
Make the Seasoning Sauce:
8 While the veggies roast, blend all the seasoning sauce ingredients in a food processor or blender until smooth.
Finish the Shrimp Boil:
10 Remove the skillet from the oven and add the shrimp, beer, and seasoning sauce. Toss everything to coat evenly.
11 Place sliced butter all over the top of the shrimp boil and return to the oven. Bake for 10-15 minutes, until the shrimp is pink and cooked through.
12 Once done, sprinkle with 1 more tablespoon of Old Bay and stir to evenly coat