Preheat the oven to 300°F and place the oven rack in the middle position. Line 3 baking sheets with silicone liners or parchment paper. If you are using parchment paper, use a pencil to trace 1 1/2-inch circles spaced 1 inch apart onto the paper to help guide you when piping the batter.
For the Italian meringue, in a small pot fitted with a candy thermometer, heat the sugar and water over medium heat until it reaches 235°F (soft ball stage). Meanwhile, in a clean, grease-free bowl of an electric mixer fitted with the whisk attachment, whisk the egg white until white and frothy. With the mixer on medium, pour in the sugar syrup in a slow and steady stream. Increase to high and whisk until a stiff and glossy meringue forms, approximately 10 minutes. Add the food coloring to the meringue and whisk until incorporated, about 1 minute more.
For the batter, sift the almond powder and confectioner’s sugar through a fine-mesh sieve into a large bowl. Discard any bits left in the sieve. Using a rubber spatula, stir in the egg white until evenly combined. Gently fold in 1/2 of the meringue into the batter. Once incorporated, fold in the remaining 1/2 of the meringue until well combined.
Transfer the batter to a pastry bag fitted with a 1/4-inch round tip. Pipe 1 1/2-inch diameter circles of batter onto the baking sheets, spacing them about 1 inch apart. The batter should yield approximately 50 cookies. Tap the sheets to allow any air bubbles to escape. Let the sheets sit at room temperature for approximately 15 to 30 minutes, or until the tops of the meringue circles are no longer sticky to the touch. Bake, one sheet at a time, in the preheated oven for approximately 15 minutes. Remove from the oven and place the sheet directly onto wire racks to cool.
Once the cookies are completely cooled, peel them off the mat or parchment paper. Spread raspberry jam on the flat side half of the cookies and top each with the remaining half of the cookies. Store the macarons in the fridge, covered in plastic, until ready to serve.
Flavor combinations for these cookies are endless. I have even tasted savory macarons flavoured with parmesan cheese. You can substitute the coloring for anything you like and also the filling to match. One of my favorites is the caramel macaron filled with some salted butter caramel. It’s worth a try!