Heat the butter and oil in a large saucepan until foaming. Fry the asparagus tips for a few mins to soften. Remove and set aside.
Add the shallots, asparagus stalks and garlic, and cook for 5-10 mins until softened but still bright.
Stir through the spinach, pour over the stock, bring to the boil, then blitz with a hand blender. Season generously and add hot water to loosen if needed. Ladle into bowls and scatter the asparagus tips over each.
Drizzle with olive oil and serve with sourdough bread, if you like.
Recipe taken from BBC Good Food, home to thousands of kid-friendly recipes.