Use good balsamic vinegar to make this syrup. The sweet/tart result offers a welcome contrast to the Greek-style yogurt's characteristic tang. Prep: 20 minutes; Chill: 1 hour; Ice-Cream Machine: 30 minutes; Freeze: 30 minutes.
Reduce balsamic vinegar and 1/2 cup sugar by half over medium-low heat in a nonreactive saucepan. Set aside.
Mix yogurt, remaining 1 cup sugar, and lemon juice until sugar dissolves. Pour into a nonreactive bowl, and chill until cold. Pour into ice-cream maker, and follow manufacturer's instructions to make frozen yogurt. Freeze 30 minutes in ice-cream bowl.
Scoop frozen yogurt into a bowl, top with berries, and drizzle with balsamic syrup. Finish with a pinch of crushed peppercorn.
*For testing purposes, we used a peppercorn mélange (mix).