Boil 1/3 cup balsamic vinegar with 2 tablespoons honey, 1 bay leaf and a pinch of salt until thick, 4 minutes. Discard the bay leaf; let the syrup cool. Beat 1 cup mascarpone, 1/2 cup heavy cream, 1 tablespoon sugar and 1/4 teaspoon vanilla with a mixer until soft peaks form. Toss 3 pints quartered strawberries with half of the balsamic syrup. Serve with the mascarpone mixture and the remaining syrup.