In a small pot on the griddle, melt butter, garlic, and parsley for the garlic herb butter. Meanwhile, steam potatoes and corn under a dome with water on medium heat until the potatoes are fork-tender.
Add sausage and onions to the potatoes and corn, drizzling with a little melted butter and seasoning with Old Bay.
Place snow crab clusters on the griddle (thaw with water if frozen) or add directly to the vegetables once thawed. Add shrimp, layering with more butter and seasoning. Toss ingredients together.
Drizzle ¼ to a whole beer around the seafood to steam the shrimp and finish cooking. Add the remaining butter, Old Bay to taste, and finish with the juice of half a lemon (reserve the other half for serving and garnishing). Serve Family-Style!
