Step 1

Measure the broth into a large microwave-safe bowl. Microwave on high for 5 minutes.

Step 2

Meanwhile, put a large pot or Dutch oven over low heat. Cut the butter into small pieces and add it to the pot. As it melts, peel and chop the onion. Add the onion to the butter. Stir and cover. Increase heat to medium. Trim the tough ends off of the asparagus as described in the blog post above. Discard ends. Chop remaining asparagus into small (1/2-inch) pieces. Add to the onions. Stir and cover. Peel and mince the garlic. Add it to the asparagus along with the salt. Stir.

Step 3

At this point the broth should be finished heating. Add it to the asparagus. Cover. Increase heat to high and bring soup to a boil. Reduce to a simmer. Cook until asparagus is tender, 2-3 minutes. While it cooks, shred the parmesan.

Step 4

Use an immersion blender to puree the soup. Add the cream and heat through over medium heat but do not bring to a simmer. Remove from heat and stir in the parmesan cheese.