With respect to pronunciation, “sk” is technically correct. In Italian, a ‘c’ before an ‘i’ or ‘e’ is pronounced ‘ch’. The added ‘h’ hardens the ‘c’. So ‘ci’ is CHEE and ‘chi’ is KEE; ‘ce’ is CHEH and ‘che’ is KEH, somewhat countintuitively for us English speakers. But of course, most people say “marasheeno,” and so it has become acceptable in the vernacular.