Slice carrots into 1/4" slices.
Chop onion into small pieces.
Chop celery into small pieces.
Chop apple into 1/2" pieces.
Saute onion and celery in olive oil over medium heat until translucent.
Add chopped carrots, apple, curry powder and pepper to pan and saute for 3 minutes. Add minced garlic and saute for 1 minute.
Add chicken stock and bring to a boil. Reduce to low heat and simmer for 30 minutes.
Strain solids from pan and add to blender with 1 cup of liquid. Let cool for 10 minutes before blending. Blend mixture, then return blended mixture to pan and mix with remaining liquid.
Serve garnished with mint leaves and yogourt or sour cream (optional).