For the crispy shrimp canapés, mix the flour with salt and pepper and roll the shrimp in the seasoned flour. Place in a large colander and shake through to remove excess flour.
Heat plenty of oil in a frying pan and fry the floured shrimp in it on both sides. Drain on paper towels.
Use a cookie cutter to cut out circles from the bread. Grate the ginger and slice the radishes. Mix mayonnaise and mustard. Spread a tablespoon of the ginger mixture on each bread circle. Spread radishes, alfalfa sprouts and fried shrimp on the canapés.
Arrange the shrimp canapés on a serving platter and garnish with chopped cilantro. Stir the remaining ginger mayonnaise with lemon juice and drizzle over the crispy shrimp canapés.