Start by adding the split red lentils and water to a small saucepan over medium heat.
Bring to a boil then lower the heat and simmer for 6 minutes, until lentils are cooked.
In the meantime, add the olive oil and onion into a medium saucepan over medium heat and saute for 2-3 minutes until golden.
Add the carrot, cauliflower, potato, diced tomatoes and vegetable stock. Season with salt and pepper.
Bring to a boil and leave to simmer for 15 minutes.
Add the cooked lentils and kale, and cook for another 5 minutes.
Remove from the heat and pour into a bowl.
Serve with fresh or toasted sourdough.