Cream together butter and sugars, on medium speed, for 4 to 5 minutes, with an electric mixer, until fluffy.
In a medium bowl, whisk together the flour and salt.
Slowly add the flour mixture to the butter mixture, on low/medium speed, just until combined. Mixture will be crumbly.
Butter an 8x8 pan and press the dough into an even layer in the bottom of the pan.
Use a fork to score the dough into rectangles of desired size.
Refrigerate dough for 30 minutes.
Preheat oven to 300 degrees F.
Bake for 50 to 60 minutes, or until the shortbread is golden brown. (Time will vary based on oven.)
Allow pan to cool completely on cooling rack.
Once cool, slice bars along the scored lines.
Melt chocolate in microwave in 30-second intervals, stirring between each interval, until completely smooth.
Dip shortbread bars in chocolate to desired look/taste. Place on parchment paper and sprinkle with any topping you like. Allow to cool. Enjoy!
