Chop the onion finely and sauté it in 3 Tbsp of olive oil.

Peel and chop all the root vegetables into cubes of roughly similar size (for even cooking).  Wash the kale, then cut it into strips.

Add the vegetables to the pot, then cover with broth or water.

Let the soup simmer at a medium heat for about 10 - 15 minutes until soft. (When you can stick a fork or knife through with little resistance).

Take the soup off the stove and blend it with a handheld blender until smooth.

Sprinkle with Piment d'Espelette (or another mild chilli powder) just before serving.