Roasted Butternut Squash Soup with Sage and Pumpkin Seeds

Bake. Heat butter in a big saucepan or Dutch oven over a medium-high flame till melted. Keep cooking, swirling pan constantly, till butter solids are gently browned and butter smells nutty, around 1 minute longer. Promptly tip in onion, celery, carrot, plus whole thyme sprigs (if using), reduce heat to mid-sized, add salt and pepper till it tastes right, and cook, mixing now and then, till vegetables are softened but not browned, around 5 minutes. Tip in stock, squash, plus bay leaves. Increase heat to high plus bring to the boil. Reduce to a bare simmer and cook till squash is completely tender, around 20 minutes. Discard bay leaves and thyme stems using tongs. Add heavy cream. Blend soup till completely smooth using an stick blender or working a batch after another in a jug blender. Taste and add salt if it needs it with salt, pepper, and lemon juice. Tip in sugar if wanted (some squashes are naturally sweeter than others). Serve.