Method

  1. Preheat oven to 375 degrees F (190 degrees C). Line 2 baking sheets with parchment paper.
  2. Beat 1 1/2 cups sugar, butter, vanilla extract, and salt together in a bowl until fluffy. Beat in eggs; add cream of tartar and baking soda. 
  3. Beat in cocoa powder, 1/2 teaspoon cinnamon, and cayenne powder. Beat in flour. Stir chocolate chips into the dough.
  4. Mix remaining 1/4 cup sugar and 1/2 teaspoon cinnamon together in a bowl.
  5. Roll heaping tablespoons of dough into balls. Roll balls in the sugar-cinnamon mixture and place on the prepared baking sheets.
  6. Bake in the preheated oven until centers are set and edges crack slightly, about 10 minutes. Cool on baking sheets for 5 minutes.