how long to cook steamed clams
4. Steam the clams. Allow the clams enough time to open their shells-this will be indicated by a burst of steam and popped-open shells, anywhere from 2â3 minutes to 5-10 minutes, depending on the type of clams.If some don't open in this time, discard them as they probably were already dead.llow the clams enough time to open their shells-this will be indicated by a burst of steam and popped-open shells, anywhere from 2â3 minutes to 5-10 minutes, depending on the type of clams.