In a large bowl, beat the butter until creamy. Mix in the sugar, egg and vanilla, then mix in the flour, baking powder and salt. Cover the dough with plastic wrap and refrigerate for 30 minutes.
Preheat the oven to 325 degrees . Using your hands and working quickly, roll a heaping tablespoon of dough into a finger shape. Place the fingers about 3 inches apart on an ungreased, parchment-lined cookie sheet. Stick a sliced almond on 1 end of each for the fingernails. Use a table knife to make three crosswise knuckle marks in the middle of each cookie. Bake until lightly golden, 20 to 25 minutes. Transfer to a rack to cool.
Meanwhile, in a small saucepan, cook the jam over low heat until it reaches a saucy consistency. Once liquefied, remove from the heat and pour into a small bowl; dip the severed end of each cookie into the sauce.