the oven to 375 degrees. Place hazelnuts on a baking
sheet, and toast in the oven for 10 minutes. Remove from oven, and immediately transfer nuts to a clean
towel. Vigorously rub
the nuts in the towel to remove as much of the skins
as possible. Set nuts aside until completely cool.
Place nuts in a food processor, and process until finely ground.
In the bowl of an electric mixer fitted with the paddle attachment, beat
butter and sugar on medium speed until light and fluffy, about 2 minutes. Add egg, and beat
until smooth, about 3 minutes. Beat
together reserved hazelnuts, flour, baking powder,
cinnamon, nutmeg, and salt.
Add to butter mixture; beat
on low until combined, about 2 minutes. Form dough into two flattened disks, wrap
each with plastic wrap,
until firm, at least 1 hour or overnight.
to 350 degrees. Have ready two baking
sheets lined with Silpats (French baking
mats; see sources) or parchment paper. Also have ready one 2 1/2-inch round fluted cookie cutter and one 3/4-inch cookie cutter. On a lightly floured work surface, roll ou
t half the dough to a scant 1/4-inch thickness. Using the 3-inch fluted cutter, cut out
cookies. With a wide spatula, transfer cookies to the prepared baking shee
ts. Using the smaller cutter, cut the
centers out of half of the cookies. Repeat rolling and
the other half of the dough. Combine the scraps from both batches, reroll and cut.
until the edges are golden, 12 to 16 minutes, rotating halfway through. Remove from oven; place on wire racks until completely cool.
Lightly sift confectioners' sugar over the decorative tops;
set aside. Spread a scant tablespoon of jam on the bottoms of each cookie, and sandwich with the sugar-dusted tops.