Preheat oven 325°
Melt chocolate, butter and espresso powder in a pan on low heat stirring until combined. Set aside to cool for 5 minutes
Whisk eggs, sugar and vanilla together
Sift flour, baking powder, and salt together. Set aside
Whisk chocolate mixture together with the egg mixture
Fold in dry ingredients until well combined
Cover with plastic and place in the fridge for at least 1 hour
Drop small spoonfuls of the batter onto a cookie sheet lined with parchment paper. Space them 2 inches apart
Bake for 11 minutes until they become slightly cracked on top
Remove from the oven and immediately sprinkle with a pinch of coarse sea salt
Let cool completely and enjoy!