Creating Purple Velvet Blackberry Macarons is a process that requires attention to detail. Follow these steps carefully to ensure success:

1. Preheat Oven: Preheat your oven to 300°F (150°C) and line baking sheets with parchment paper.
2. Sift Dry Ingredients: In a bowl, sift together almond flour and powdered sugar. Set aside.
3. Whip Egg Whites: In a separate bowl, whip the aged egg whites until frothy. Gradually add granulated sugar and continue to whip until stiff peaks form.
4. Add Color and Flavor: Gently fold in the purple gel food coloring and vanilla extract into the egg whites.
5. Combine Mixtures: Carefully fold the sifted almond flour mixture into the egg whites. Use a spatula to combine until the mixture flows like lava.
6. Pipe Shells: Transfer the batter to a piping bag fitted with a round tip. Pipe small circles on the parchment paper, leaving space between each.
7. Rest the Shells: Allow the piped shells to rest for 30 minutes, or until a skin forms on the surface.
8. Bake: Bake in the preheated oven for 15-20 minutes. The shells should be firm to the touch.
9. Cool Completely: Once baked, let the macarons cool on the baking sheet for a few minutes, then transfer to a wire rack to cool completely.
10. Prepare Filling: In a bowl, mash the fresh blackberries. In another bowl, beat the softened butter until creamy. Gradually add the powdered sugar, vanilla extract, lemon juice, and the mashed blackberries. Mix until smooth.
11. Assemble Macarons: Pair the cooled macaron shells with similar-sized partners. Pipe a dollop of blackberry filling onto one shell and gently press the other shell on top.
12. Chill: Place the assembled macarons in the refrigerator for at least 30 minutes to allow the flavors to meld.

By following these steps, you’ll create stunning Purple Velvet Blackberry Macarons that are sure to impress!