1: Melt the chocolate with the butter, add the coffee, mix and let it cool.
2: In a bowl, add the eggs, butter, vanilla, and sweetener, and mix well, preferably with an electric mixer.
3: Mix the flours separately.
4: Combine both mixtures and add the oats and crushed pistachios.
5: Pour everything into a well-greased rectangular silicone mold or lined with parchment paper.
6: Bake at 180°C (350°F), pre-heated, with circular heat or air for about 35 to 40 minutes.
7: Be careful not to overcook as the brownie should remain moist inside.
