Combine squid and prawn paste and seasoning ingredients together in a large mixing bowl. Throw meat against the sides of the bowl continuously for about a minute. Divide mixture into 5 portions.
Spread each portion on to a slice of bread. Use the back of a spoon to spread out the paste evenly on the bread. Place another slice of bread on top. Press down lightly.
Steam the prepared slices of bread in batches over rapidly boiling water for 34 minutes. Remove and cool completely.
Trim the bread slices and cut into triangles. Coat the pieces with combined flour mixture. Dip each piece in beaten egg whites and then coat with breadcrumbs. Place on a tray and refrigerate for 3040 minutes.
Heat oil for deep-frying in an electric fryer or deep saucepan to 170°C. Fry the bread slices in batches for 23 minutes or until crisp and golden. Remove and drain on kitchen paper. Serve immediately with chilli sauce.