Heat olive oil in a large pot over medium heat. Add the diced onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic, ground cumin, and turmeric powder, cooking for an additional minute until fragrant.
Add the chopped carrots and rinsed lentils to the pot, stirring to combine all ingredients.
Pour in the vegetable broth, bring the mixture to a boil, then reduce the heat to a simmer. Cook uncovered for about 20 minutes, or until the lentils and carrots are tender.
Once cooked, use an immersion blender to puree the soup until smooth. If you don't have an immersion blender, carefully transfer the soup in batches to a blender.
Return the blended soup to the pot and stir in the coconut milk. Season with salt and pepper to taste. Heat through on low for about 5 minutes.
Serve hot, garnished with fresh cilantro and a lemon wedge on the side for a refreshing twist.