In a small bowl, place the chocolate, the 1/4 C cocoa powder and coffee and set aside.
In a small pan, placed on the stove to high heat, place the butter and oil and mix until the butter melts, then let it sit for the butter misture to start almost boiling. Pour this over the chocolate and let it sit for 2 minutes, then mix using a whisk until everything´s well combined.
In a different big bowl, place the sugar, brown sugar, vanilla an salt.
Crack the eggs in a different bowl. Then incorporate them into the sugar bowl and beat using a mixer. Keep mixing for 10 minutes at medium to high speed. The mixture will lighten in color and thicken in consistency.
Start adding the chocolate mixture to the sugar and eggs one while still beating, little by little. Once done continue to beat for 1 more minute.
Mix in the flour and the 1/2 C cocoa powder using a rubber spatula as quickly as you can not to take the air out of the batter.
Pour the batter onto a rectangular baking pan, previously buttered and lined with parchment paper, and smooth it out using the rubber spatula.
Bake at 350°F (180°C) for 20 minutes.
Once the 20 minuetes have passed take them out of the oven and slam them on the kitchen counter to crack the top and even it all out.
Bake them for 25 more minutes.
Take them out, and let them cool down completely. Cut them out into small squares or rectangles of about 2×2 inches (5×5 cm).