leek and butter bean soup — dead simple, proper warming

Made a big pot of this yesterday and honestly it's become my default October soup. Welsh leeks obviously, because it would be criminal not to at this time of year — they're everywhere right now and the ones from the market are a completely different thing to the watery supermarket ones. Basically soften two large leeks in a bit of rapeseed oil, add a couple of garlic cloves, then tip in two tins of butter beans (keep the liquid, don't drain them), about 700ml of good vegetable stock and a generous amount of fresh thyme. Simmer for 20 minutes then blend about half of it so you get that texture where it's creamy but still has some bite. Finish with a squeeze of lemon and black pepper. That's it. Nutrition-wise it does a lot of quiet work. Leeks are a good source of prebiotic fibre — specifically fructooligosaccharides, which feed beneficial gut bacteria. Butter beans are carrying the protein here, roughly 8g per 100g cooked, plus they're high in magnesium which most people eating a fairly standard diet are low in. The research on magnesium and sleep quality is actually quite solid, mind you, so an autumn soup that might help you sleep better isn't the worst thing. Blod kept coming to sit next to me while I was cooking this which is either very sweet or she was just after the bread I had on the side. Rhys had two bowls so I'm calling it a success.