Beat 1/2 cup butter and 1/4 cup sugar until pale. Add flour and ground almonds to form a soft dough.
Press dough into a 8 inch square pan that has been greased and lined with parchment paper. Bake shortbread at 350 degrees F (175 degrees C) for 20 to 25 minutes, or until pale golden brown. Leave in pan until cool.
To Make Topping: Cook 3/4 cup butter, 3/8 cup sugar, syrup, and sweetened condensed milk in a saucepan on low heat. Bring to a boil, stirring constantly. Boil for 5 to 7 minutes until it has thickened and has a pale caramel color.
Spread caramel on cooled shortbread, and let set about 40 minutes. Melt chocolate over low heat. Spread melted chocolate on top of caramel and sprinkle on toasted almonds.