These foolproof Lemon Raspberry Macarons have the perfect classic French Macaron smooth crisp shell and chewy center with the most delicious raspberry lemon buttercream filling sandwiched in between.
In the bowl of an electric mixer with the whisk attachment, beat the egg whites on medium until foamy. Add the cream of tartar and salt and continue to beat. While beating, add about 1 tablespoon sugar at a time. Increase speed to medium-high and mix until stiff peaks. You should be able to turn the bowl upside down without it sliding. Add the lemon juice and gel food coloring and beat on medium until combined.
Add the almond flour and powdered sugar by sifting it into the meringue (this is the second time sifting). Use a rubber scraper and gently fold the ingredients together by scraping the sides clockwise, starting at the bottom and then cutting down through the middle once you get to the top. The batter will thin up as you mix. Test the batter by dropping some back into the bowl. It will fall off the spatula like thick lava and the edges of the dropped batter will dissolve within ten seconds.
Preheat the oven to 300 degrees Fahrenheit and bake for 18-20 minutes. Place pan on a cooling rack for 15 minutes and then slide the parchment onto the cooling rack and let the macarons cool completely.
Place in a piping bag and squeeze about 2-3 teaspoons onto the bottom of a cooled macaron. Place another macaron on the frosting to make a sandwich and gently press until the filling spreads to the edge of the cookie.
Refrigerate the cookies in an airtight container for at least 3 hours before serving and up to 5 days. Freeze for up to 4 months.