Brown Butter Shortbread Cookie Sandwiches {Recipe}

These adorable shortbread cookie sandwiches remind me of a Milano cookie... but they're wayyyy better. I mean, brown butter... that's all you need, right?
 
What You Need:
1 cup (2 sticks) unsalted butter
6 Tbsp heavy cream (divided)
3/4 cup powdered sugar
seeds from 1 vanilla bean

1 tsp. salt
2 1/4 cups all-purpose flour
4 oz. chopped dark chocolate (or chocolate chips)
Yield: 2-3 dozen cookie sandwiches. (I used a 1-1/2" round cutter, so I got about 30.)

Make the Cookie Dough

Melt two sticks of butter on medium heat in a light-colored pan. (This is important because you need to see the color change.) 

Stirring constantly, watch the butter as it first forms a white foam...

Then gets separated and very bubbly and spluttery...

Then the bits begin to turn light brown on the bottom of the pan.

REMOVE from the heat immediately, when the browning happens. It can burn quickly. You will smell a major difference when it starts to brown. It smells like heaven.

Immediately pour into a small heatproof bowl. Set in the refrigerator to cool to room temperature. (You could also set over a bowl of ice water.) You want it to be the consistency of softened butter before you add the remaining ingredients. 

If you do not wait, your cookies WILL NOT TURN OUT!

When the butter has set, add 2 Tbsp. of heavy cream and beat with mixer until creamy. Add 3/4 cup powdered sugar and seeds from 1 vanilla bean, and mix until combined. 

On the lowest speed, add 2 1/4 cups flour and 1 tsp. salt. Mix until coarse crumbs form. 

You want to mix this as little as possible. The more you mix or knead it, the more you build up gluten, and the cookies get tough and chewy, not crispy and airy.

Using your hands, press the dough into a ragged ball in the bowl. Dump out onto a lightly floured board, and knead very gently into a disk about 2-3" thick. Wrap in plastic wrap and let rest in the refrigerator for 20-30 minutes.

Preheat oven to 325-degrees (F). Line 2 cookie sheets with parchment paper.

On a lightly-floured board, roll to 1/4" thick, and cut into shapes. Arrange on the baking sheets. (These should not spread, so you can place them rather close together.) Place baking sheets into the freezer, and let freeze for 15 minutes. Bake at 325-degrees (F) for 12-16 minutes, until the edges are barely turning golden brown. You may want to rotate your pans halfway through baking to ensure they're evenly baked, if your oven doesn't cook evenly.

Let cookies cool completely.

While the cookies cool, make the ganache filling. Heat 1/4 cup (4 Tbsp.) heavy cream for about 30 seconds in the microwave. Immediately add 4 oz. chopped chocolate to the hot cream and let set for 30 seconds.

Mix with a small whisk or fork... it will look separated and gross at first, but will then come together as a beautiful, gorgeous ganache. You need to let it set until it is the consistency of thick pudding before you can make the cookie sandwiches.

Add 1 tsp. of the thickened ganache to one cookie, and press the other cookie into the top. 

Let them set for 15-20 more minutes before serving, or the ganache will squirt out.

Alternative flavors for the filling:

- Add oil-based flavorings to the ganache to make mint-chocolate, raspberry-chocolate, orange-chocolate, etc.

- Use a thick jam to make a fruit-flavored filling.