English Toffee Shortbread

Why I Love This Recipe
This is tried and tested!! It's one of my English Mom's recipes.
Ingredients You'll Need
Shortbread Base:
1 1/2 sticks butter or margarine
1 1/4 C flour
1/4 C sugar
Toffee Filling:
1/2 C Eagle Brand condensed milk
1 stick butter or margarine
2 Tbps Lyles Golden Syrup or 2 Tbps Karo + 1/4 C sugar
Topping:
1 C powdered sugar
1 Tbsp chocolate syrup
boiling water
Directions
Shortbread Base:
Rub butter and sugar together.
Add flour 1/2 C at a time and rub into butter sugar mixture.
Press into a small jelly roll pan or cookie sheet. Bake at 350° for 10-15 mins. or until golden brown.
Toffee Filling:
Mix all ingredients together in a sauce pan. Bring to a boil stirring constantly. Boil for 10 mins. Remove from heat and beat 3-4 mins. Spread over baked shortbread. Let cool.
Topping:
Frost with milk cooking chocolate (which according to Mom is not available in the US).
SO:
Mix powdered sugar with chocolate syrup and enough boiling water to make a stiff but spreadable frosting.
Frost. Let dry in frig.
Cut into bars.
Will keep well in a covered plastic container. (In the frig if it's hot out)