1 1/2 cups ground almonds
1 cup icing sugar
3 egg whites
Red liquid Food Coloring (not gel), 8 drops for pale pink macaroons or 24 for dark
1/2 cup sugar
1. With the rack in the middle position, preheat the oven to 180 °C (350 °F). Line two baking sheets with parchment paper.
2. In a food processor, process the almonds and icing sugar into fine powder, about 2 to 3 minutes. Set aside.
3. In a bowl, beat the egg whites with the food coloring until soft peaks form. Gradually add the sugar, beating constantly until stiff peaks form. With a spatula, firmly combine with the ground almonds Mixture and mix until the meringue fall and soften slightly.
4. With a pastry bag fitted with a 7-mm (1/2-inch) in diameter plain tip, shape 2.5-cm (1-inch) in diameter Macarons, spacing them about 5-cm (2-inch) apart. (The batter should fall slightly. Otherwise, it is not quite soft enough. Remove from the bag and mix again). Hit the baking sheet flat on a work surface two or three times to slightly spread the batter.
5. Bake, one sheet at a time, for about 12 minutes, leaving the oven door ajar with a wooden spoon. The macarons should not brown. Cool completely on the baking sheet. (For smaller macarons, bake from 8 to 10 minutes. They should therefore be baked on two different baking sheets.)
(Basic Macaron Buttercream Filling)
7 tablespoons unsalted butter, softened
2 egg yolks
1/4 cup granulated sugar
3 1/2 tablespoons milk
1 teaspoon vanilla extract
1. Cut butter into pieces, and mash with a spatula until the consistency resembles mayonnaise.
2. In a small bowl, Whisk the egg yolks, then add the granulated sugar, and whisk until the mixture lightens to an off-white  and you can no longer see the granules of sugar. Add the milk, and whisk to combine.
3. Pour the egg mixture into a small saucepan, and heat over low heat, whisking frequently to ensure that the mixture does not curdle or scorch. Cook until the mixture becomes thick and custardy, like pudding.
4. Pour the egg mixture back into its bowl, and whisk constantly until it returns to room temperature. Whisk in the butter in three batches, add the vanilla, and stir until smooth and all ingredients are fully combined. Pipe or spread onto one macaron half and sandwich between the other.