Add the carrots, cauliflower, split peas, broth and water. Bring to a boil. Reduce the heat to low and let it simmer with the lid on for about 50-60 minutes, or until the vegetables and split peas are cooked.
Add the thyme, rosemary, salt and pepper and stir well. Adjust according to your preference.
Optional: use an immersion blender or high-speed blender to achieve a smoother consistency. If using a stand-up blender, allow the soup to cool for 30 minutes before blending.