Prepare your vegetables: Trim the woody ends from your asparagus, chop the stalks into 1-inch pieces, and slice your cleaned leeks into thin half-moons.

In a large pot, melt butter over medium heat. Add the sliced leeks and a pinch of salt. Sauté for about 8 minutes until soft and translucent.

Add minced garlic and cook for another minute.

Add the chopped asparagus stalks and vegetable broth. Bring to a boil, then reduce heat and simmer for 15 minutes until asparagus is very tender.

Blanch the reserved asparagus tips in boiling salted water for 2 minutes, then drain and set aside for garnish.

Remove the pot from heat and puree the soup until smooth using an immersion blender or a standing blender.

Stir in heavy cream and fresh lemon juice. Season with salt and pepper to taste.

Serve hot, garnished with the blanched asparagus tips.