Chocolate-caramel shortbread sandwiches

I've been in a bit of a mad search for the perfect sablé recipe.  I'm completely obsessed with the sandy French butter cookies from the north of France.  The best ones I've had came from a tiny bakery called Grain de Vanille in a little town named Cancale on the rugged Brittany coast.  That-little-bakery-that-could is small in size but not stature, as it is owned and operated by the Michelin-three-star chef Olivier Roellinger.  We haven't been back there in a couple of years, and I'm positively aching for some of those sablés (though chef Roellinger calls them Galettes de Cancale.) 

I'm not quite ready to share the sablé recipe yet, I've got a really good one now, but I'm not sure if it's the ultimate yet.  I'll share it when I get there.  Meanwhile, my mad search resulted in loads of perfectly delicious, buttery sablé cookies - albeit not quite the caliber of le Grain de Vanille yet - and I had to do something with them.  That's when this idea came to me.  Cookie sandwiches!  The obvious choice is chocolate ganache - who doesn't love chocolate ganache?  But I wanted to make something even more special.  Yes, and what about some gooey salted butter caramel - didn't the NY Times just claim that everyone now loves salty caramels?  (As for me, I've loved them for ages thank you very much!)

But filling cookie sandwiches with gooey, salty caramel turned out to be a bit of a design problem.  The caramel oozed out of the cookies before it had enough time to set.  So here's where the ganache came into play again.  I piped the ganache along the edges of the cookie, forming a levy so I could pour the caramel inside.  Topped with another butter piece of cookie, the sandwich is now ready to be devoured.  The caramel will still ooze out once bitten into, but by then I am beyond caring - and so will you, too. 

You can use just about any butter cookie or shortbread recipe you like.  If you need some place to start, Dorie Greenspan's "punitions", as interpreted by Deb of Smitten Kitchen, is a very good one. 

This quantity of ganache and caramel will be enough to make about 24 (2-3 inch wide) cookie sandwiches.  (Doubling the recipe on Deb's blog should do.)

Chocolate Ganache
100g or 3 1/2 oz very good quality dark chocolate
120ml, 1/2 cup cream

Salted Butter Caramel
120g, 1/2 cup sugar
60g salted butter, at room temperature
100ml, 1/4cup+2tablespoons cream

Chop up the chocolate into small pieces.  Add the cream to a medium pot saucepan over low heat and bring to a gentle simmer.  Add the chopped chocolates to the pan, turn the heat off, and let sit for two minutes to melt.  Whisk until the ganache is smooth and let rest until cool down a bit.  Fill a medium pastry bag with the ganache.  If you don't have a pastry bag, you can improvise one with a regular ziplog bag.  Add the ganache to the ziplog bag, seal it close and cut a hole in one corner so you can squeeze out the chocolate.  And there you have it, your pastry bag.

Let the ganache cool down just a little bit, then pipe it along the edges of a cookie to form a sort of levy.  Do this to half the amount of cookies or shortbread you made.  Let sit to cool down and set a bit more.  Meanwhile, you can make the caramel.

In a medium pot, add the sugar and let it melt over medium heat.  Shake the pan occasionally to make sure all the sugar is melted.  Stir if you need to.  Add cream to a small pot and bring to a gentle simmer.  When the sugar melts and turn amber, add the cream and stir vigorously to mix well.  Add the butter in small chunks and stir to blend.  Set the caramel aside to cool down until lukewarm but still liquid.

Fill another pastry bag with caramel, and pipe it into the middle of each cookie, making sure the caramel stays inside the ganache so you don't make a mess.  Cover each one with another cookie to make cookie sandwiches.