To make the crust: Preheat oven to 400 degrees F. Sift the flour, sugar, and salt into the bowl of a food processor. Add the pine nuts and butter and pulse until the texture resembles coarse cornmeal, about 10 to 15 seconds. With the motor running, add the egg yolks. If the dough is too dry to form a soft ball when pressed, add ice water 1 tablespoon at a time and pulse to mix. Do not over process; the dough should not be processed for more than 30 to 40 seconds after adding the liquids.

Transfer the dough to a sheet of waxed paper or plastic wrap. Form the dough into a flat circle. Enclose tightly in plastic wrap and refrigerate at least 1 hour or up to 1 day.

Press the chilled dough in a 10 to 11-inch fluted tart pan and use fingers to press it over the bottom and up the side of the pan. Roll over the edges. Use a fork to prick the shell all over. Cover and chill for 1 hour.

Line the chilled dough with foil or parchment paper smoothed carefully into all of the corners. Line with dry beans, rice, or pie weights. Bake for 10 to 12 minutes, just to set the crust. Remove from the oven and carefully lift the foil and weights. Return to the oven 8 to 10 minutes, until the edges barely begin to color. Set aside to cool.

Prepare the filling: In a mixing bowl, beat the egg, egg yolk, and the 1/4 cup sugar until they double in volume and become pale in color.

In a double boiler over medium heat, melt the chocolate and butter. Slowly whisk in the liqueur and vanilla until completely blended. Slowly whisk the egg mixture into the double boiler and cook, whisking constantly, 3 to 4 minutes. Remove the top pan from the heat and set aside to cool.

Whip the cream with 1 tablespoon sugar until soft peaks form. Slowly drizzle in the coffee and beat until stiff peaks form. Fold the whipped cream into the cooled chocolate mixture. Pour the filling into the tart shell, cover, and refrigerate for at least 3 hours before serving, or up to 3 days.

Prepare the topping: Whip the cream with the sugar until soft peaks form. Slowly drizzle in the coffee and beat until stiff peaks form.

To serve, cut the tart into wedges. Spoon a generous dollop of the whipped cream on each slice and decorate with a chocolate coffee bean, if desired.