Yield 30 ASSEMBLED HAZELNUT SHORTBREAD COOKIES
These buttery Hazelnut Shortbread Cookies are filled with a bright Roasted Strawberry Buttercream that wonderfully showcases summer's bounty.
For the roasted strawberries: Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper. In a large bowl, toss the strawberries with the maple syrup. Transfer to the prepared baking sheet. Roast for 30 minutes. Set the baking sheet over a rack and let the strawberries cool completely.
For the cookies: In a mixing bowl, combine the ground hazelnuts, flours, baking powder, and salt. In a second bowl, beat the butter, sugar, and vanilla together until the mixture is fluffy and pale, about 3 minutes. Add the egg yolk and beat well. Add the flour and hazelnut mixture and mix at low speed until the dough is just combined, about 1 minute. Gather the dough together into a ball, split in halves, then wrap each portion in plastic wrap. Refrigerate the dough for 30 minutes.
Remove the dough from the refrigerator and let it rest at room temperature for 15 minutes. Set a large piece of parchment paper onto a work surface, place the first ball of dough in the center, then cover with another piece of parchment paper. Roll the dough out until 1/4-inch thick (the dough may crack during the process; simply pat it back together using your fingers). Using a 2-inch round cookie cutter, cut out as many shapes as possible. Use an offset spatula or a knife to carefully transfer the cut-out cookies onto the prepared baking sheets, setting the cookies about 1 inch apart to allow for some light spreading. Gather the scraps, reroll, and cut out new shapes, repeating until there is no dough left. Repeat with the second ball of dough.
Bake the first sheet of cookies for 15 minutes, until pale golden on the edges. Cool the cookies for a few minutes on the baking sheet, and then transfer to a wire rack to cool completely. Bake the remaining cookies.
For the buttercream: Scrape the cooled roasted strawberries to a measuring cup and, using a stick blender, puree to a fine consistency. Measure out 1/2 cup (125 ml) puree for the frosting. (If you have any puree leftover, add it to oatmeal, smoothies, or just eat it with toast or a croissant!)
In the bowl of a stand mixer, or in a large mixing bowl if using a hand mixer, beat the butter and vanilla seeds together until creamy. Lower the speed and add the strawberry puree, beating until fully incorporated. Gradually add the sugar at low speed, then beat at medium-high speed for a couple of minutes, or until the frosting is light and fluffy.
Assemble the cookies: Using an offset spatula, spread a thick layer of buttercream on the underside of a cookie. Alternatively, you can also transfer the buttercream to a pastry bag fitted with a round tip, and use it to pipe neat little mounds of buttercream onto cookies. Cover the frosted cookies with a second cookie, very gently pressing to spread the frosting all the way to the sides (shortbread cookies are crumbly, so make sure to proceed with care.) Repeat to assemble all cookies.
Store in an airtight container in the refrigerator. The assembled cookies are best enjoyed within 3 days.
Recipe Credit: Marie Asselin
Recipe by Food Nouveau at https://foodnouveau.com/recipes/desserts/cookies/hazelnut-shortbread-cookies/