I never did get to try this dish in Portugal but the idea of shellfish and pork together fascinated me. However, research shows this to be more in the use of smoked or cured pork than fresh. Both are a popular combination in Portugal, not only because they have very good pork and seafood. Legend has it that during the Inquisition these combinations were invented as a sort of culinary double-whammy to test one’s Christian zeal as pork and shellfish were proscribed to both Jews and Moslems. A cataplana is a hinged metal container that can be clamped shut. A pan with a tight fitting lid works too.