Błędnie: I was sure I'd bought everything, but it turned out we'd ran out of sugar powder. I definitely need it to make the cake- will you please go and buy some? Poprawnie: I was sure I'd bought everything, but it turned out we'd ran out of caster sugar. I definitely need it to make the cake- will you please go and buy some?
"Cukier puder" to 'caster/ castor sugar'. "Cukier puder" przeznaczony do robienia lukru to 'icing sugar' lub 'powdered sugar'.