Serves 6 large bowls, 8 small
6 yellow crookneck squash (about 2-1/2 cups)
3 tablespoons butter
1 small white onion, diced
1 bunch of dill, to yield 4 tablespoons, chopped
4 cups vegetable broth
1 cup well-shaken buttermilk
Wash the squash and slice into discs about 1/2 inch thick.
In a Dutch oven, melt the butter over medium-high heat. Drop in the diced onion and sauté until soft and translucent. Stir in half of the chopped dill (about two tablespoons) and cook for a further minute. Season with salt. Add the sliced squash to the pot and gently stir to coat with butter, onions and dill. Cover the pot and leave the squash to steam for a few minutes. Pour in the broth, stir well and bring to a boil. Reduce the heat to low, cover the pot and simmer for 30 minutes, stirring a few times, until the squash is completely soft. Remove from the heat and leave to cool.
When the squash is cool, transfer the squash and broth to a blender, in batches, and puree each batch until smooth. Pour through a strainer into a large bowl When all the soup is strained, chill in the fridge until nice and cold. Whish the buttermilk and the remaining dill into the soup and season with salt to taste, then return to the fridge until thoroughly chilled.