Peel the squash, scoop out the seeds, and chop into 2” pieces. Sauté onion in stock pot over medium heat with a pinch of salt and olive oil for 5 minutes. Add apples, curry and cook for a few more minutes. Next, add the squash and just enough stock to cover the onions, apples and squash. Simmer for approximately 30 minutes or until the apples and squash are completely cooked through.
Remove from heat and purée mixture in a blender in 2-3 batches until smooth or if preferred, use an immersion blender in the stock pot. Return mixture to the stove, add maple syrup, lemon juice, and salt and pepper to taste. Taste and adjust seasoning if necessary. Soup may need to be thinned with a bit more stock. Cook on low heat for 5-8 more minutes. Serve in soup bowls and garnish with a dollop of crème fraîche and chives. Serves 4-6.