Step 1

Place potato in a large saucepan. Cover with cold water. Bring to the boil over high heat. Reduce heat to medium. Cook, uncovered, for 10 minutes or until tender. Drain. Return to pan over low heat. Cook, tossing for 1 minute or until liquid has evaporated. Transfer to a large bowl. Roughly mash. Cool for 5 minutes.

Step 2

Add tuna, lemon rind, chives, egg and 1/4 cup breadcrumbs to potato. Stir to combine. Using damp hands, shape breadcrumbs on a plate. Lightly coat patties in breadcrumbs.

Step 3

Heat oil in a large frying pan over medium-high heat. Cook patties for 3 to 4 minutes each side or until golden and heated through.

Step 4

Spread cut sides of rolls with half the mayonnaise. Top roll bases with spinach, patties and remaining mayonnaise. Sandwich with roll tops. Serve.