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