Heat the oil in your soup pot over medium heat, then stir in the onions and carrots. Saute for about 10 minutes. Add the cumin and stir well. Decrease the heat, cover, and let the vegetables sweat for ten minutes.
Add the lentils and pour in enough of the water to cover. Bring to a simmer, then reduce the heat to medium low and cook for twenty minutes, or until the lentils and carrots are tender. Add more of the water as needed as the lentils soften and expand.
Remove from the heat, stir in the apricots and any remaining water, and season with salt. Use an immersion blender to puree until smooth; alternatively working in batches, puree in a regular blender until smooth. Take care not to over salt this soup. The right amount will bring out the flavor of the apricots but leave the onions in the background. Serve hot.