In a blender, add 320 grams fresh (not frozen) raw king prawns, 1 egg, 1/4 teaspoon sea salt, 1/4 teaspoon MSG, 1/4 teaspoon caster sugar, 1/4 teaspoon ground white pepper, 1/4 teaspoon ground black pepper,1/4 teaspoon Chinese 5-spice, 1 teaspoon oyster sauce, Dash fish sauce, 1/2 teaspoon sesame oil, 1 tablespoon chopped garlic in oil, 1 tablespoon rice wine, 1 tablespoon water and 1 teaspoon potato starch. Blend to a smooth paste.
Unwrap 2 400g 'toastie' style white bread loaves (or any other thick white bread). Spread 250 grams white sesame seeds out on a large plate. Using a flat spatula, spread 2 tablespoons of the prepared prawn mix onto a bread slice, spreading all the way to the edges of the bread. Pour the sesame seeds onto a large plate and press the bread, prawn side down, firmly into the sesame seeds to coat. Flip the prepared prawn toast slice over, cut into 4 triangles and arrange on a sheet of baking paper.
Repeat the process with the remaining prawn mix until all of the mix is used up, layering prawn toast slices between sheets of baking paper. Open-freeze for 6 hours or overnight, then transfer frozen prawn toast slices to a large freezer-safe food bag.
To fry prawn toast pieces from frozen: Heat oil for deep frying to 165C/330F. Carefully drop prawn toast pieces into the hot oil with the prawn and sesame side facing down and fry for 2 1/2 minutes. Carefully flip prawn toasts with tongs and fry for another 2 minutes or until golden and crispy. Remove from the oil, drain off any excess oil and arrange on a serving plate. Serve with sweet and sour sauce or sweet chilli sauce.