FOR PASTRY: In a bowl, combine the butter and confectioners’ sugar. Using a wooden spoon, cream together until very light and fluffy. Add the egg and salt and beat until combined. Add the flour and stir until the mixture comes together to form a dough. Divide the dough in half and pat each half into a ball. Wrap in plastic wrap and refrigerate 1 ball for 2-3 hours or as long as overnight. Reserve the other half to make another tart; it can be frozen for up to 2 months.
Preheat an oven to 325 degrees.
On a lightly floured work surface, roll out the ball of dough into a round about 12 inches in diameter and 1/8-1/4 inch thick. Drape the round over the rolling pin and transfer to a 10-inch tart pan with a removable bottom. Ease the pastry into the tart pan, pressing it gently against the bottom and sides. Trim the edges even with the pan rim. Place in the refrigerator to chill for 15 minutes.
Prick the bottom and sides of the pastry with a fork. Bake until golden, 10-12 minutes. Transfer to a rack to cool. Leave the oven set at 325 degrees.
FOR FILLING: In a large bowl, whisk together the eggs, brown sugar, corn syrup, molasses, melted butter, vanilla and cinnamon until well blended. Add the salt, almonds and chocolate and mix to coat evenly.
Pour the filling into the tart shell and bake until the center is set, 35-40 minutes. To test, press gently on top with your fingertips. Transfer to a rack and let cool.
TO SERVE: Remove the pan sides and, using a spatula, slide off the pan bottom onto a serving plate. Cut into wedges and serve with whipped cream.