1.Sauté leek in olive oil until soft. Add kale and cook until wilted. 2.Add broth and cook for 30 minutes on low heat and let cool for 10-15 minutes or until temperature reaches 120°F (65°C). 3.Place soup into the Vitamix container and secure lid. 4.Select Variable 1. 5.Turn machine on and slowly increase speed to Variable 10, then to High. 6.Blend for 45 seconds until smooth. 7.Pour mixture back into pot and heat for 10 minutes, or just until it begins to simmer. Season to taste with salt and pepper.