Start by trimming the tough ends off the asparagus, then chop them into 2-inch pieces. Peel and dice the potatoes into small chunks.
Heat the olive oil in a large heavy-bottomed pot over medium heat until shimmering and fragrant, about 1 minute. Add the minced garlic and sauté for about 30 seconds until it releases a warm, garlicky aroma, being careful not to burn.
Add the diced potatoes to the pot and stir for 1-2 minutes, coating them in the aromatic oil and garlic. Then pour in the vegetable broth, bringing it to a gentle simmer.
Cook the potatoes for about 10 minutes until they are tender but still hold their shape. Then toss in the chopped asparagus and cook for another 3-4 minutes, until the asparagus is bright green and just tender, but still with a slight crunch.
Transfer the cooked vegetables and broth into a blender. Blend until silky smooth, then return the pureed soup to the pot and warm gently. If it’s too thick, add a splash more broth or water and stir well.
Stir in lemon zest or a squeeze of lemon juice to brighten the flavors. Taste and adjust the seasoning with salt and freshly cracked pepper.
Ladle the hot soup into bowls, garnishing with a few whole asparagus tips or fresh herbs if desired. Drizzle with a little extra olive oil for a finishing touch, then serve immediately for the best vibrant flavor and silky texture.
