For these brownies, you do not need to melt chocolate, all you need is good dark cacao (use unsweetened, natural cocoa powder). The cooking process is really easy, and will not take a lot of time. Give it a try, and I'm going to make some coffee and have a slice or two. —Katya Moskalenko
2. Line the baking pan with parchment paper and spray it with cooking spray.
3. Combine the butter, sugar, cocoa, and salt in a medium metal (or glass) bowl and fit the bowl on top of a pot of simmering water. Stir the mixture until the butter is melted and you have a paste.
4. Remove the bowl from the pot and let it cool for a few minutes.
5. Add the egg, stirring occasionally. Add the flour and stir until it disappears. Stir in the nuts. Transfer everything in your lined baking pan. (You can sprinkle the mixture with flaky sea salt, like Maldon.)