Make the shortbread by creaming together the butter and sugar for a couple minutes until combined. Add the vanilla extract and salt, and mix in. Add the flour and mix until distributed. The dough is going to look extremely crumbly. You should still be able to press it into an 8×8 pan.
Refrigerate for 30 minutes.
Preheat oven to 350 degrees F.
Combine all almond syrup ingredients in a saucepan, and bring to a full boil over medium high heat. Let it cook for 2 minutes, then remove from the heat.
Pour the almond topping on top of the shortbread and bake for 20 minutes. Let it cool in the pan, then cut it into squares. Enjoy!