Use an immersion blender to blend until smooth. If you don't have one, place the lentil mixture in a blender. Remove center piece of blender lid (to allow steam to escape); secure blender lid on blender. Place a clean towel over opening in blender lid (to avoid splatters). Blend until smooth. Return lentil mixture to pan over medium heat. Add remaining 1/2 cup broth, 1 cup water, and pumpkin to pan; cook 3 minutes or until thoroughly heated. Stir in ginger and lemon juice.
Serve with a dollop of yogurt, chopped cilantro and toasted pumpkin seeds