Tuna Carpaccio with Lime & Passion Fruit

A fresh, tangy starter to serve on a hot summer evening in the garden. You need to have total confidence in your fishmonger, of course, to make sure you get the very freshest fish. It needs to be shiny and ruby red, with no smell, or at the very most a pleasant suggestion of sea air. The combination of lime and passion fruit also works well with raw scallops.