1. Preheat oven to 350 F / 180 C.
2. Brush 8x8 pan (I have used pyrex glass pan) generously with butter.
3. In a small bowl add apple cider vinegar/vinegar, milk and keep aside for 5 minutes.
4. Grind sugar in a spice grinder/mixie
5. In a large bowl, sift all purpose flour, baking soda, salt, cocoa powder and powdered sugar.
6. Add instant coffee powder to milk and stir well.
7. In another bowl, add grated chocolate and oil. Microwave for 30 seconds.
8. Add it to the milk mixture and stir well.
9. Now add the wet ingredients to dry ingredients(sifted mixture).
10. Stir well with a spatula until all the ingredients are combined.
11. Add coarsely chopped walnuts.
12. Pour batter into the pan and bake it for 25 minutes.
13. Allow it to cool in the pan for 10-15 minutes.
14. Then remove it from the pan and allow it to cool little longer.
15. Cut into slices and enjoy these irresistible eggless brownies.

Recipe courtesy: Food for 7 Stages of Life