1-Preheat your oven to 300°F (150°C) and line two baking sheets with parchment paper, a Teflon sheet, or a silicone mat to get ready for baking.

2-Sift the hazelnut flour, almond flour, and powdered sugar together twice, then discard any large, chunky bits up to 2 tablespoons to keep the batter smooth.

3-In a clean bowl, mix the egg whites, fine granulated sugar, cream of tartar, and a pinch of salt; whisk on medium speed until soft peaks form, then keep going until you get stiff peaks that hold sharp ribs.

4-Sift the dry ingredients into the meringue and gently fold with a silicone spatula until everything is fully mixed; continue folding until the batter flows slowly, forming a figure eight that dissolves in about 10 seconds, aiming for around 50 folds without overdoing it.

5-Transfer the batter to a piping bag with a round tip and pipe 1.5-inch rounds, spaced about 1 inch apart on the prepared sheets.

6-Tap the sheets firmly on the counter to release air bubbles and use a toothpick to pop any big ones left for smooth tops.

7-Let the piped macarons sit on the counter for 15 minutes to form a skin, which helps them bake up perfectly.

8-Bake one sheet at a time on the middle rack for 15 to 18 minutes without convection; place an empty baking sheet on the top rack to avoid browning, and check if they’re done by gently touching they should be firm with no wobble.

9-Cool the macarons on the sheet for 10-15 minutes, then move them to a wire rack to cool completely.

10-Pair the shells by size, pipe a thick layer of chocolate hazelnut spread on the flat side of one shell, and press another shell on top so the filling reaches the edges.

11-Store the filled macarons in an airtight container in the fridge for at least 8 hours, or preferably 24 hours, to let the flavors blend and the shells soften.

12-Before serving, bring them to room temperature for about 30 minutes to enjoy the best texture and taste.