Mix the water and yeast and let it froth for 5 minutes. If it doesn't, the yeast has lost its efficacy, don't continue, try again.
Add the rest of the ingredients except for the butter and beat until shiny.
Add the butter and knead until the dough passes the window pane test.
Shape them into 40g rounds.
Flatten dough with the sides thinner than the center. Wrap the dried prawn filings. Put a piece of cheese on the top of the bun.
Proof the bread for 40 to 1 hour, until it is double its original size.
Bake at 200C for 9 minutes. Rebrush the top with butter if desired.