Salted Caramel Filled Shortbread Bars

I originally saw the recipe for these "Salted Carmel Butter Bars" on Pinterest, and Jennifer requested them for her birthday today. So naturally that means they are everywhere on the web by now. I ended up tweaking the recipe a little, and changing a some things. Since people have asked me for the recipe, I thought I would write those thoughts up in one easy to access post. 

First, these things are dense and rich. One of those square bars up there is more than enough for one sitting. I probably should have cut them smaller to be honest. The original recipe makes a full 9x13 pan of these, which in my opinion - unless you are baking for some kind of event - is way too much. It also means that you use a full pound of butter, which after adding the sugar and flour was almost too overwhelming for my KitchenAid mixer. 

Second, make your own caramel. Trust me on this one. My favorite flavor combination is most definitely salted carmel. Since I started making my own caramel, I've lost the taste for those wrapped store caramels. Plus depending on the state of your pantry, making carmel is cheaper than those wrapped ones. The recipe below will make enough for about two half pint jars of it, so I like to make a batch and keep some on hand for baking emergencies, to spoon over ice cream and into coffee.

Third, I swapped out the original shortbread recipe - butter, granulated sugar. powdered sugar and flour, for a similar sturdy shortbread recipe that I have used in the past. 

Salted Caramel Filled Shortbread Bars

Originally from Pip and Ebby / Shortbread adapted from Real Simple

2 cups (4 sticks) unsalted butter
1 cup sugar
1/2 teaspoon salt (if using salted butter, leave out the salt)
4 1/2 cups all-purpose flour
1 tsp sea salt

(Depending on your mixer, you could also halve this recipe, and make two batches of shortbread).

Heat oven to 325° F. Combine the butter, sugar, and salt in a mixer and beat until light and fluffy. Slowly add the flour and mix until smooth. Divide the dough in half, and press one half into a greased 8-inch square pan. Place the other half of the dough in the refrigerator.

Bake 20-30 minutes or just until the shortbread begins to turn golden brown. Let cool on a wire rack for 15 minutes.

Make caramel (see below). Pour caramel over shortbread in pan so it forms an even layer. Sprinkle with sea salt.

Take remaining dough out of the refrigerator, and crumble evenly over the carmel layer.

Bake until the filling is bubbly and the crumbled shortbread topping is firm and lightly golden, about 25-30 minutes.

Salted Carmel Sauce (from Brown Eyed Baker)

(If you haven't made your own caramel before, I would recommend looking at David Lebovitz's 10 Tips for Making Carmel post.)

2 cups granulated sugar
12 tablespoons unsalted butter, at room temperature, cut into pieces
1 cup heavy cream, at room temperature
1 tablespoon fleur de sel (or any other flaky sea salt)

Add the sugar in an even layer over the bottom of a heavy saucepan, with a capacity of at least 2 or 3 quarts. Heat the sugar over medium-high heat, whisking it as it begins to melt. You'll see that the sugar will begin to form clumps, but that's okay. Just keep whisking and as it continues to cook, they will melt back down. Stop whisking once all of the sugar has melted, and swirl the pan occasionally while the sugar cooks.

Continue cooking until the sugar has reached a deep amber color. It should look almost a reddish-brown, and have a slight toasted aroma. This is the point where caramel can go from perfect to burnt in a matter of seconds, so keep a close eye. If you are using an instant-read thermometer, cook the sugar until it reaches 350 degrees F.

As soon as the caramel reaches 350 degrees, add the butter all at once. Be careful, as the caramel will bubble up when the butter is added. Whisk the butter into the caramel until it is completely melted.

Remove the pan from the heat and slowly pour the cream into the caramel. Again, be careful because the mixture will once again bubble up ferociously.

Whisk until all of the cream has been incorporated and you have a smooth sauce. Add the fleur de sel and whisk to incorporate.

Set the sauce aside to cool for 10 to 15 minutes and then pour into your favorite glass jar and let cool to room temperature. You can refrigerate the sauce for up to 2 weeks.