I simply adore Biolea olive oil from the Astrikas Estate in Crete. Pressed from only koroneiki olives, it is superbly silky and smooth, with herbaceous aromas that give way to a pleasant peppery finish. I use it to make wonderful vinaigrettes with chardonnay vinegar and strawberry or raspberry preserves. It is also fantastic drizzled over pasta or fresh mozzarella.
Peel grapefruit with a sharp knife down to the flesh, removing all the rind and membrane. Cut the sections free, slicing carefully along the membranes.
Combine the orange juice, white wine vinegar, and olive oil in a bowl and whisk together. Add salt and pepper to taste.
Toss arugula and grapefruit with vinaigrette. Top with ventresca tuna, and finish by lightly sprinkling on Marcona almonds and Meski olives.