Blackberry Macarons: Delicious Recipe w/ Step-By-Step Tutorial

Name: Blackberry Macarons
Prep time: 20 min
Cook time: 18 min
Total time: 1 h 8 min
Yield: 20
Ingredients: 110 g Egg whites, aged; 1/2 cup Your favorite blackberry jam; 140 g Almond flour, superfine; 1/4 tsp Cream of tartar - optional; 110 g Granulated sugar; 1 Pink and regal purple gel food coloring - optional; 291 g Powdered sugar; 2 g Salt, fine; 4 g Vanilla extract; 113 g Butter, unsalted; 15 g Heavy cream; Large, flat baking sheets; Kitchen scale; Fine Mesh Sieve; 1 Large piping bag (18-inch); 2 Small piping bags (12-inch); Small Round Piping Tip; Round Piping Tip - Ateco 805; Silpat Mats (or parchment paper); Stand Mixer or Electric Mixer