Let’s break down the process into detailed, easy-to-follow steps. Macarons can be tricky, so precision is key!

Make the Macaron Shells:

1. Process Dry Ingredients: Place the almond flour and 1 ¾ cups of the confectioners’ sugar in a food processor; pulse until thoroughly mixed to ensure the almond flour is very fine.
2. Sift: Pass the almond flour mixture through a fine-mesh sieve; discard any large pieces that remain. This is crucial for achieving smooth macaron shells.
3. Whip Egg Whites: Place the egg whites and salt in a very clean bowl of a stand mixer fitted with a whisk attachment; whisk on medium-low speed until frothy.
4. Add Sugars: Slowly add the superfine sugar; whisk until dissolved, 1-2 minutes. Slowly add the remaining ½ cup confectioners’ sugar; increase the speed to high and whip until the meringue is glossy and stiff peaks form, 1-2 minutes. If desired, add in enough food coloring to achieve desired color.
5. Fold in Dry Ingredients: Gently fold the almond flour mixture into the meringue, a third at a time. This is a crucial step. You want to deflate the meringue slightly, but not completely. The batter should be smooth and flow like lava.
6. Macaronage: Using the side of a spatula, smooth the batter up the sides of the bowl several times to remove air bubbles and ensure there are no lumps; do not overmix. Run the spatula down the center of the bowl; the line in the batter should remain visible for a moment before the mixture runs back into itself. This is the “macaronage” step, and it’s key to achieving the right batter consistency.
7. Prepare for Piping: Position a rack in the upper third of the oven; preheat oven to 300°F (150°C).
8. Pipe Macarons: Transfer the batter into a pastry bag fitted with a #7 or #10 round tip. Pipe 1 3/8-inch rounds onto a parchment-lined tray about 1 inch apart.
9. Tap and Rest: Tap the tray against the counter 2-3 times to remove excess air bubbles. Let the macarons rest until no longer wet or sticky to the touch, 30-60 minutes. This resting period allows a skin to form on the top of the macarons, which is essential for developing the signature “feet” during baking.
10. Bake: Bake, 1 tray at a time, until the cookies rise about 1/8 inch to form “feet,” 14-16 minutes, rotating the tray halfway through baking.
11. Cool: Remove the tray and let the macarons cool completely; repeat with the remaining trays. Once the macarons have cooled completely, remove from parchment.

Make the Buttercream Filling:

1. Cream Butter: Beat the softened butter in a mixing bowl until creamy.
2. Add Sugar and Strawberry Powder: Gradually add the confectioners’ sugar and strawberry powder, beating until smooth and well combined.
3. Incorporate Remaining Ingredients: Add the heavy whipping cream, vanilla extract, and salt. Beat until light and fluffy. Add pink food coloring, if desired.
4. Fill a Pastry Bag (Optional): Transfer the buttercream to a pastry bag for easier filling.

Assemble the Macarons:

1. Pair Shells: Match up similar-sized macaron shells.
2. Pipe Filling: Pipe or spread a small amount of buttercream onto the flat side of one shell. Top with a tiny dollop of strawberry jam (about 1/2 tsp per macaron).
3. Sandwich: Gently sandwich the filled shell with its matching shell.
4. Mature (Optional but Recommended): For the best texture and flavor, place the assembled macarons in an airtight container and refrigerate for 24-48 hours. This allows the filling to soften the shells slightly, creating that signature macaron texture.

These instructions are very detailed, and crucial for a perfect result.