1) Place four tomatoes and 125ml of stock in a blender. Cover and blend altogether until the tomatoes are completely pureed. Add the remaining vegetable stock and pulse for a few more seconds to combine.
2) Place mixture into a saucepan or stove-top safe fondue pot, add the sliced ginger and roughly chopped coriander, cover and place on medium heat until the mixture comes to a boil.
3) Whilst the sauce is heating, take the seafood out of the refrigerator and begin to arrange the fish on a plate.
4) As soon as the sauce has come to the boil, transfer the pot onto the heat station on the table, and continue to keep the mixture at boiling point. If the liquid seems to have reduced, just add more vegetable stock.
5) Take a skewer and a piece of fish, skewer the fish and dip it into the sauce. Wait just a few seconds, until it cooks, then add dipping sauces, to taste.
Combine the mayonnaise, lemon zest and juice in a mixing bowl.
1) In a food processor place both heads of the ginger and pulse the ginger until it has become a pulp. Place the mayonnaise into a mixing bowl.
2) Place a clean kitchen towel or cheesecloth over a separate bowl; transfer the pulp onto the towel. Pick up the towel by all four corners. Twist the kitchen towel very tightly over the mixing bowl and let the ginger juice pour into the bowl. Stir in the mayonnaise, mix well and serve.