Making maple syrup can be brutal work, as I found out when I spent a week in the Vermont woods with maple syrup makers Howie and Stephan Cantor. With only a few people, tapping holes in sixty acres of maple trees is hard enough. Then the sap starts running, and the work goes round the clock for days, feeding logs to a fire and boiling the sap down. Fortunately, compared to the labor involved in making the syrup, making this tart is a breeze.