Preparation

1. Cut the tip off a large piping bag and fit it with a large plain tip. Twist the bag just above the tip and push the twisted portion into the tip.
2. Place the piping bag in a tall glass and fold the top ends over the sides to hold it open. Set aside.
3. Sift almond flour into a bowl and measure out 150 grams sifted. Discard any lumps. Sift 180 grams of powdered sugar into the same bowl and mix.
4. Wipe a bowl with vinegar or lemon juice to remove grease. Add salt and egg whites, then beat on medium-high speed until bubbles form (30 seconds to 1 minute).
5. Gradually add granulated sugar to the egg whites while beating. Add sugar slowly and whip for 20 to 30 seconds before each addition.
6. Continue whipping until glossy, reaching stiff peaks. Test by dipping the whisk; the tip should not curl over.
7. Add food coloring and vanilla to the meringue and mix to combine.

Macaronage

1. Gently fold the almond flour mixture into the meringue in 3 additions. Mix until the batter reaches a lava-like consistency.
2. Transfer the batter to the piping bag without spooning it in. Pipe macaron shells onto a baking sheet, leaving 1 inch between each.
3. Bang the baking sheet on the counter to pop air bubbles and set aside for 30 to 60 minutes to dry.
4. Bake in a preheated 315°F oven for 12 to 15 minutes. Test doneness by pressing a shell; it should not jiggle.
5. Cool completely on the baking sheet and match similar sized shells together.
6. Pipe filling onto one shell and sandwich with another.