Pre-heat your oven to 160C Fan/180C/350F/Gas Mark 4, line a 8" square tin with greaseproof paper. I grease the tin first with a little butter to help the paper stick to it
To make the shortbread biscuit base mix the golden caster sugar and butter together into a bowl until creamy, using a spoon, or an electric mixer if you have one
Add the plain flour and vanilla, and mix in
Tip the mixture into the tin and press it down with your fingers until compact and even
Bake the shortbread biscuit base for 20-25 minutes, until lightly golden
For the topping, put the maple syrup, light brown sugar and butter into a pan and melt them together on a low heat
Bring the mixture to a boil and boil for 3 minutes - stirring constantly - then remove from the heat
In a bowl whisk the eggs, vanilla and milk together
Add the egg mixture to the maple syrup mixture very slowly, add a little bit and whisk as you add it
Then stir in the chopped pecans
Pour the topping over the cooked base and put it back in the over for 30 minutes
Let it cool fully before removing from the tin and cutting into squares, I also highly recommend chilling it in the fridge to make it easier to cut
Store in an airtight container in a cool place and eat within 3 days
Video
Notes
Make sure your butter is at room temperature before you start baking the shortbread, and that your eggs are at room temperature before you make the maple caramel layer.
I used unsalted butter for both the shortbread and the maple caramel. You can use salted butter if you like, it won't make it taste salty, instead it will balance out the sweetness. However, I do prefer to use unsalted butter and add my own salt as then I can control the salt levels. You can also use a baking spread, but butter tastes much better in my opinion. It's not that baking spread tastes bad, just that real butter is richer and creamier.
You must use plain flour (also known as all purpose flour) for the shortbread, self raising flour will make the shortbread rise, which you don't want to happen.
I used golden caster sugar for the shortbread layer, but caster sugar (also known as superfine sugar) will work too.
I used light brown soft sugar for the maple caramel layer, but caster sugar (also known as superfine sugar) works well too.
Although I provide cup measurements, I highly recommend weighing your ingredients out using digital kitchen scales. It is the most accurate way to measure ingredients and will ensure the best results. Digital scales are very low cost and can be purchased for around £12 ($16.50) .
For teaspoon (tsp) and tablespoon (tbsp) measurements, please use measuring spoons and not the type of spoons you eat with. Again this will ensure accuracy and provide the best results.