Decadently Dense Walnut Brownies

1. Preheat oven to 350°F.
2. Grease an 8×8″ square pan. Set aside.
3. In a medium saucepan over low heat, melt butter. Add the chocolate and stir until melted.
4. Remove the pan from the heat and stir in the sugar, vanilla, coffee powder and salt until combined.
5. Beat in the eggs one at a time.
6. Add the flour and stir vigorously for 1 full minute. The batter should become smooth, glossy and elastic.
7. Stir in chopped nuts, if using.
8. Scrape the batter into the prepared pan and bake until the centre feels almost set, about 30 minutes. Do not overbake!
9. Let the brownies cool completely in the pan, then cut into 16 squares.