Store-bought or homemade pie pastry to fill a 9-inch tart pan
3 large eggs
1¾ cups lightly toasted coarsely chopped pecans
1 cup pure maple syrup
2 tablespoons (¼ stick) unsalted butter, melted
2 teaspoons pure vanilla extract
¼ teaspoon salt
Pecan halves, for garnish (about 40)
Lightly sweetened whipped cream (optional)
Place an oven rack at the lowest position and set a baking sheet on the rack. Preheat the oven to 350°F. On a lightly floured surface, roll out the pastry into an 11-inch circle. Carefully transfer the pastry to a 9-inch tart pan with a removable bottom. Press the dough into the bottom and sides of the pan. Then press the dough over the top edge of the pan to remove the excess. Use the remaining dough to make a leaf cutout for the top of the tart.
In a medium bowl, whisk the eggs and then add the chopped pecans, maple syrup, butter, vanilla, and salt. Whisk to combine and then pour into the pastry shell. Line the edge of the tart with slightly overlapping pecan halves, if desired.
Place the tart pan on the preheated baking sheet and bake for 30 to 35 minutes, until the filling is set and the pastry is lightly browned. Let cool in the pan on a wire rack. Remove the rim of the pan and place the tart, still on the pan bottom, on a serving platter. Serve with whipped cream, if desired.
To make the decorative leaf cutout, roll out the extra dough on a lightly floured surface. Cut out a leaf shape with the tip of a sharp knife. Place the cutout on a piece of aluminum foil. Sprinkle with sugar and bake alongside the tart until light golden brown, about 20 minutes. Let cool and place on top of the baked tart.