In stand mixer with paddle attachment, cream butter and sugar until light and fluffy. Add vanilla and almond extract. Add dry ingredients and mix until mixture is moistened, but still crumbly.
Press mixture into sheet pan lined with parchment. Sprinkle top with sugar, and roll out until smooth and even. Pierce the top of the shortbread with a fork or meat tenderizer.
Bake at 350°F for approximately 20-25 minutes until top is light golden brown.
For chocolate truffle topping
Over double boiler, melt butter, chocolate, sugar, and cocoa together. Remove from heat. Add egg and stir until blended.
Spread chocolate truffle topping over shortbread. Sprinkle with toasted chopped almonds. Bake for 5-10 minutes until mixture is set. Cut into bars while still warm.