Marinate barramundi fillet in fish sauce and lemon zest for about 30 minutes. In the meantime, blanch the mint leaves for one minute in boiling water and cool down in ice and water. Leave a few leaves aside for garnish. Strain and squeeze blanched leaves before blending them in a food processor with oil until very smooth. Season buttermilk with a few drops of lemon juice and a touch of salt. Slice barramundi in thin slices and lay them on a flat plate. Peel cucumber and dice into 2cm thick rounds. Season with fish sauce marinade and place cucumber on plate, alternating with barramundi slices.
Mix mint oil and buttermilk and pour a good amount around the plate. Grate cauliflower with a cheese grater over the top of the dish. Sprinkle caviar over fish and garnish with mint leaves to finish.
300g Infinity Blue barramundi fillet
1 small purple cauliflower
1 small Lebanese cucumber
2 bunches of mint
25ml Thai fish sauce
80ml olive oil
Recipe adapted from: https://australianbarramundi.com.au/recipes/barramundi-sashimi/