Preheat oven to 350°F.
In a medium-sized bowl, whisk together the egg, vanilla and sugar until uniform.
Add melted butter and salt, and whisk to combine.
Whisk flour into wet mixture until dough is formed.
Press into greased 10” tart pan with your fingers, evenly distributing dough within the pan.
Bake for 15–20 minutes, until lightly golden at edges. Watch carefully. Remove from oven and set aside.
Meanwhile, work on the almond topping. In a medium-sized saucepan, bring sugar, butter, vanilla and milk to a boil.
Add the slivered almonds and salt and cook on high heat for 5 minutes, until a pale caramel color is achieved.
Pour almond mixture on top of crust and spread into an even layer.
Increase oven temperature to 400°F.
Put tart on sheet pan (some bubbling over of almond may occur) and bake for another 15–20 minutes. Tart is ready when deep golden brown color is visible.
Cool on wire rack for 5 minutes, then remove from pan to finish cooling.
Serve with creme fraiche or vanilla ice cream and plenty of black coffee.
One of Portugal's well-known legends tells of how almond trees came to be part of the landscape of the southern region when an Arab prince, concerned that his wife from a northern country, missed the snow so much she was depressed. The prince ordered the planting of almond trees, whose blossoming created the illusion of fields covered with snow. As to the validity of this romantic and highly lyrical legend, who cares?! The Portuguese love their almonds and this Tarte de Amendoa is simply sublime and wonderful.