Bring a pot of salty water to a rolling boil. Grab each asparagus stalk at both ends and gently bend - it will break naturally at the tender to tough transition point. I think I learned that from Alton Brown. When the water is boiling, add the asparagus and blanch for about a minute, then plunge it into a big bowl of ice water. When it is completely chilled remove and pat dry.
Cut the potatoes in 8ths, chop the white part of the fennel and add the potatoes, fennel and onion to a pot with the broth. Add a couple grinds of pepper and a pinch of salt. Bring to a simmer and continue to simmer until they are all quite tender. Meanwhile cut just the tips off the asparagus and chop the stalks.
Once the potatoes and friends are tender add in the asparagus stalks and the half n half. Simmer a few more minutes, then add a handful of chopped fennel greens and turn off the heat. Use an immersion blender (or move the soup to a blender) and blend it until it's uniform but still has a bit of texture and flecks of red and green. Taste and adjust the seasoning. Return to the heat and stir in the asparagus tips and the lemon zest and leave it just long enough for them to get warm. Serve topped with chives and crisp proscuitto.
** for the proscuitto, you can just lay thin slices between paper towels and put them on a paper plate, and microwave them on and off until they are crispy. Easy peasy!
I work in databases by day, but creativity is my outlet. Food - imagining it, making it, sharing it. And art, I come from a family of artists and have been collaging in my garage studio. You can see my work on Etsy in my shop AbbiesGarage https://www.etsy.com/shop/AbbiesGarage?ref=search_shop_redirect