Chocolate Brownies - The Way You Cook

Ingredients

• 10 and 1/2 Tbs unsalted butter
• 6 oz unsweetened baking chocolate
• 250 g sugar
• 1/2 ts salt (Fleur de Sel)
• 2/3 cup AP flour
• 3 eggs, at room temperature
• 1 ts pure vanilla extract
• a handful of walnuts (optional)