Walnut meringue sandwich cookies with vanilla cream

Ingredients:

Cookie

• 0.5 tbsp. blanched hazelnuts
• Whites of 3 large eggs, room temperature
• 1/4 tsp cream of tartar
• 1/4 teaspoon salt
• 0.5 cup granulated sugar
• 1 tsp vanilla extract
• 1/4 cup powdered sugar

Filling

• 4 tablespoons unsalted butter, room temperature
• 3/4 cup powdered sugar
• A pinch of salt
• 0.5 tsp vanilla extract
• 1/4 cup cranberry or redcurrant jam

Preparation:

1. Position oven racks in the upper and lower thirds of the oven and preheat to 350°F (175°C). Spread the hazelnuts on a rimmed baking sheet and toast for 9-11 minutes until golden brown. Let cool, then chop finely. Reduce the oven temperature to 250°F (110°C) and line 2 baking sheets with parchment paper.
2. Bake some cookiesIn a large bowl, beat the egg whites, cream of tartar, and salt with a mixer on medium speed until soft peaks form, about 3 minutes. Increase the mixer speed to medium-high and beat in the granulated sugar, 1 tablespoon at a time. Continue beating until stiff peaks form, 6-8 minutes. Stir in the vanilla extract. Add the chopped hazelnuts and sift the powdered sugar over the mixture. Stir with a rubber spatula.
3. Transfer the meringue to a pastry bag fitted with a large round tip. Pipe 5cm (2in) circles onto the prepared baking sheets, keeping the tip as close to the sheet as possible, about 2.5cm (1in) apart.
4. Bake, rotating the baking sheets halfway through, until the meringues are dry and come away from the parchment paper, 1.5 to 2 hours. Turn off the oven and leave the meringues in for another 30 minutes. Then transfer them to wire racks to cool completely.
5. Meanwhile, prepare the filling.In a bowl, beat the butter, powdered sugar, and salt with a mixer on medium speed for 1 minute. Increase the mixer speed to medium-high and beat in the vanilla extract; beat until fluffy, about 3 minutes. Spoon 1 teaspoon of cream and 1/2 teaspoon of jam onto the flat side of each meringue half. Top with the remaining meringues.