Preheat oven to 325 degrees F. Line an 8 inch square metal pan with nonstick foil.
In a mixing bowl, beat the eggs, yolk and sugar with an electric mixer for 2 minutes. Add the oil gradually, then add the cake meal and cocoa powder, stirring until smooth. Stir in the espresso powder, salt, nuts and chocolate chips.
Scrape mixture into the pan and sprinkle more nuts on top if desired.
Bake for about 30-32 minutes or until brownies appear set. Let them cool completely.
I like to chill them a bit before I lift them from the pan and cut with a knife.