Place oysters in a colander over a boiling pot, and steam until the shells open. Transfer the oysters to a grill, or steam for an additional five to nine minutes. Oysters usually take 10 to 20 minutes to fully cook depending on the recipe and the size of the oysters. Oysters are edible as soon as the shells open.
Steaming oysters requires a colander with a lid or a steaming pan. Most recipes for steamed oysters include adding the seasoning and flavoring components into the water and allowing the steam to carry them up to the oysters. For example, one recipe is 3 cups of water with 1/4 cup of white wine, one clove of garlic, 2 tablespoons seafood seasoning such as Old Bay, 1/2 teaspoon paprika and a bay leaf. Lay the oysters flat into a steamer or colander in a single row. For more oysters, use a colander rack. Steam for 10 minutes, or until all of the oysters are open. Consider removing smaller oysters within a few minutes of them opening in order to avoid overcooking. Most recipes call for a white wine sauce to serve with the oysters, but this is a matter of personal preference.