Heat oven to 350 degrees and line 2 baking sheets with parchment paper.

In a large bowl, whisk the eggs until blended.

In another large bowl, sift together the confectioners’ sugar, cocoa powder, cinnamon or coffee if using and salt. Whisk this into the eggs, changing to a spatula as this becomes too thick to whisk. Stir in vanilla extract and chocolate chunks.

Use a 2 tablespoon scoop and drop dough onto baking sheets to make about 24 cookies. They will be tall and I pressed each one down just a bit with my finger. Leave about 1 1/2 inches between them, but they really do not spread. Sprinkle with flaky sea salt.

Bake, rotating from front to back, and top to bottom, halfway through, until set around edges, cracked on top and slightly underbaked in the middle, about 10 to 12 minutes. Transfer to a rack to cool completely.

Store in an airtight container.