Heat 1 Tablespoon of oil in a small pot over medium heat. Add curry paste and sauté for 1 minute to release the aromatic flavors. Add ¼ Cup of coconut milk and whisk into the curry paste. Remove from pot and keep to the side.
In a large pot heat 2 tablespoons of oil over medium-high heat. Add onions, celery, carrots, leeks, garlic, and about 3 cups of butternut squash. Cook, stirring occasionally for 5 minutes. Remove half the mixture and keep to the side.
Add lentils, 4 cups of broth, and the curry paste mixture you had to the side. Bring to a boil, reduce heat, and simmer for 25 minutes.
Remove from heat and blend with an *immersion blender in a quick motion 3-4 times to slightly break up the mixture. Add the original vegetable mixture that you have put to the side back into the pot with the remaining broth and simmer for another 15 minutes. Remove from the heat and stir in the remaining coconut milk. Season with salt and pepper to taste.
Serve and garnish with lime wedges and chopped cilantro.
*The cups of butternut squash do not have to be exact. The worst-case scenario is that the stew will be on the thicker side. You can thin this out with more broth if needed.
*If you do not have an immersion blender, blend half the mixture (in batches) on the lowest setting of your blender for 2-3 seconds