Cribbed and adapted from here.
Preheat oven to 325.
In large bowl (largest yellow bowl), melt
1/2 c cocoa powder, or a little more
1/2 c butter (1 stick)
Optional: 1/8t of espresso powder
and stir until smooth. (I use the microwave, about 1 min; stir; about 1 min more); let cool.
While that's cooking and cooling, toast
1 c pecans (or walnuts, but pecans are better)
in a cast iron pan and then chop or break up into pieces no more than about 1/2" in size.
Place and 8 x 12 piece of buttered parchment paper over the bottom and sides of an 8x8 baking dish, butter side up. Butter the visible sides of the baking dish.
Whisk in (once the cocoa mixture is cool enough not to cook the eggs!)
1/2 c sugar, or a little less
2 eggs, one at a time
1 t vanilla extract
In another bowl, combine
1/4 c flour
1/2 c sugar, or a little less
pinch of salt
the pecans
and then add to the cocoa-butter mix and stir until just combined. Pour into the prepared baking dish and top with
a light dusting of Maldon salt flakes
Bake 29 - 33 min (for a metal baking dish) or 29 min (glass). They're done almost as soon as you can smell them.