Place potatoes, milk, butter, salt and pepper in saucepan; bring to a boil. Reduce heat to medium-low; simmer 10 to 12 min., or until potatoes are soft. Add salmon; cook 3 to 5 min. until potatoes are very tender and fish is cooked through; drain. Roughly mash. Gently stir in egg, mayonnaise, chives, mustard and lemon juice just until combined; keep the mixture chunky.
Divide into 18 portions and form into 1/2-in. (1-cm) thick patties (texture will be moist). Coat each patty in breadcrumbs. Chill 15 min.
Meanwhile, heat large saucepan filled with 1-in. (2.5-cm) deep canola oil on medium heat. Working in batches, fry cakes 1 to 2 min. per side until golden brown. Drain on paper towel-lined tray. Serve with tzatziki or mango salsa, if desired.
These salmon cakes also make great kids’ lunches or dinners.
Freeze cooked cakes. Reheat in 180˚C (350˚F) oven until hot (internal temperature is 70˚C (158˚F).