Preheat the oven to 160 C . In a bowl combine the flour, cocoa, baking soda and salt. Set aside.
Melt the butter and Dark chocolate together over low heat . Remove from heat and add the vanilla extract.
Combine the eggs and sugar and beat at medium speed with a hand mixer until light and fluffy, about 3 minutes. Add the chocolate mixture and stir until well combined.
Add the flour mixture and stir until just combined. Fold in the chocolate chips or chocolate chunks.
Drop 1-1/2 tablespoon portions 2-inches apart onto a baking sheet lined with parchment paper or butter paper.
6. Bake for 13-14 minutes , they should be slightly underbaked so the inner part is chewy and soft. Remove the whole sheet of parchment to a cooling rack and cool until just warm and set.
Enjoy this Starbucks style cookie with coffee or milk .