Preheat oven to 350 degrees F. Butter a 9x12 baking pan. On low heat, melt chocolate in saucepan, stirring constantly. Set aside to cool.
In a separate bowl sift flour, baking powder, sugar, and salt. Melt butter, add olive oil and mix in one egg at a time.
Add in vanilla, and then chocolate. Fold in dry ingredients - don’t over mix batter. Pour mixture into a pan smoothing off the top. Sprinkle chocolate chunks on top of batter. Bake for 25-30 minutes until brownies pull away from side of pan.