Toast 1 tablespoon sesame seeds in a pan over a low heat, stirring for 2 minutes, when they should give off a nice aroma. Set aside. Drain a large can of brined green olives and put them in a bowl. Wash an orange thoroughly, scrubbing gently under cold, running water. Dry it and carefully peel off the zest without any white pith. Cut the zest into the thinnest strips you can manage and add to the olives. Cut the orange into segments, again without pith, and add these. Coarsely crush 1 teaspoon black peppercorns with the sesame seeds. Stir this into 4 tablespoons extra-virgin olive oil with 12 chopped mint leaves (not spearmint!). Toss the olive mixture in this and put to marinate in the fridge for 2 hours before serving.