How to Make It
In a small saucepan, combine the vinegar, salt, sugar and currants and warm over moderate heat just until the sugar dissolves. Remove the saucepan from the heat and let cool slightly. Drain, reserving 2 teaspoons of the pickling liquid.
In a large bowl, toss the squash with the greens, basil, olive oil, currants and the pickling liquid. Transfer to a platter. Top with the hazelnuts, garnish with cheese and serve.