A hazelnut shortbread forms the base of these mini-tarts, which are filled with raspberries and chocolate ganache.
In a food processor, chop hazelnuts to the texture of coarse sand.
In a standing mixer fitted with a paddle attachment, blend butter and brown sugar 2 minutes.
Add flour and chopped hazelnuts, and mix briefly until dough forms a ball. Wrap in plastic and chill at least 30 minutes, up to 1 day.
Meanwhile, make the ganache:
Pour chocolate chips into a heat-safe mixing bowl. In a heavy saucepan, heat cream over medium-high setting until it just begins to simmer.
Remove from heat immediately and pour hot cream over chocolate chips. Stir steadily until all chocolate is melted and blended. Set aside, or refrigerate up to 3 days. Assemble the tartlets:
Preheat oven to 350°. Thoroughly grease a mini-muffin pan with butter.
Form 2 teaspoons dough into a ball and press into tart cup, creating a well for the filling with your thumb. Repeat with remaining mixture.
Bake shells until golden brown, about 15 minutes. Remove from oven.
If dough has puffed during cooking, gently press down with your thumb.
When shells are cool, turn and lift carefully to remove from pan.
Warm raspberry preserves in your microwave or in a small saucepan over low heat. Spoon approximately ½ teaspoon preserves into each shell.
Warm chocolate ganache in your microwave or over low heat. Using a pastry bag (or a plastic sandwich bag with a hole cut in one corner), neatly pipe ganache into shells, approximately 1-½ teaspoons per shell, until almost filled.
Press a whole raspberry, upside down, into ganache. Tartlets are best when served within 24 hours.