Salted Caramel & Toasted Walnut Shortbread Bars

I am really at a loss for words with these bars. They are so delicious, they have taken the words right out of me.

I actually made them for the first time a week ago, and couldn't get a photo I liked enough before they all got eaten. I couldn't very well post an inferior photo of such a superb treat, so I just had to make them again! The ways in which I suffer.

The base for these bars is a brown sugar shortbread. It is rich and buttery (without being greasy), it is smooth, almost creamy and melts in your mouth. On top of it is a layer of caramel. Beautifully smooth caramel, soft caramel, salted caramel. The caramel contains large pieces of toasted walnuts, whose bitterness are a perfect counterpoint for the sweetness of the other elements. Topping all of this is a light sprinkling of coarse sea salt. Wow.

These bars are surprisingly easy to make, which may or may not be a good thing. I haven't yet decided. Another thing I haven't decided is whether chocolate would improve upon these already-so-close-to-perfection bars. I'll let you know when I figure it out.

Salted Caramel & Toasted Walnut Shortbread Bars

adapted liberally from Cookin' Canuck

For the Crust:

9 tablespoons (4 1/2 ounces) unsalted butter, softened

1/4 cup firmly packed dark brown sugar

2 tablespoons granulated sugar

1/2 teaspoon salt

1 1/2 cups unbleached white flour

For the Filling:

6 tablespoons (3 ounces) unsalted butter

1/4 cup firmly packed dark brown sugar

scant 1/4 cup granulated sugar

1/4 cup agave

1 tablespoon + 1 1/2 teaspoons heavy cream

1/2 teaspoon salt

1 cup coarsely chopped walnuts, toasted until golden brown

1/2 teaspoon vanilla extract

coarse sea salt for finishing

Preheat oven to 375. Line an 8x8 baking dish with a piece of parchment, letting it hang over by a couple of inches on each end. In the bowl of a stand mixer fitted with the paddle attachment, cream butter, salt and sugars until light and fluffy, about 2 minutes. Add flour and stir until just combined. Press firmly and evenly into pan, prick all over with a fork and place in fridge for 2o minutes. Then bake for 18-20 minutes, or until golden brown. Place on cooling rack while you make the filling.

To make the filling: Reduce oven temperature to 325. Place butter, sugars, agave, heavy cream and salt in medium sized saucepan over medium-high heat. Bring to a boil, stirring constantly. Continue to boil for about three minutes, or until caramel is thickened and coats the back of a spoon. Remove from heat, stir in toasted walnuts and vanilla, and pour into crust. Place back in the oven and bake for 10-15 minutes, or until mixture has begun to bubble. Remove from oven and let cool on rack, or to speed things up you can place pan in the refrigerator. When filling is lukewarm, sprinkle with coarse salt. Wait until bars are completely cooled, then remove from pan lifting by the overhanging parchment. Peel parchment off, and cut with a sharp knife.