Kale and Chickpea Soup with Lemon

Set a dutch oven or large saucepan over medium heat, pour in the olive oil. Finely dice the shallots and add to the pan, stirring to coat with the oil. Make 4 or 5 long horizontal slices in the celery stalk and dice. Add this to the pan and stir. Finely chop the rosemary leaves and stir into the pan together with the bay leaf and the chili flakes. Peel the garlic clove and crush it, using the flat of your knife and the heel of your hand, so that it is still whole, then add it to the pan. Add the chickpeas and the kale and stir. Pour in the hot stock, let it come to a boil and turn down the heat. Add salt if you're using unsalted stock. Let it simmer for 20 minutes until the kale is tender. Squeeze in the juice of half a lemon. Check the seasoning and adjust to taste. You might want more lemon or salt -- it all depends on what stock you've used. Working in batches or in the pan itself, if you have a stick blender, blitz until you have the texture you like. I like mine to still have a few chickpeas and pieces of kale throughout, so I set aside a couple of ladlefuls and use a stick blender to blitz the rest. Serve hot, floating a couple of slices of lemon on top of each serving. Pass round the Parmesan cheese for everyone to help themselves. It's lovely with toasted crusty bread.