Here's the recipe with my added notes. I cook it for a good half hour at least before letting it cool some and then use the blender. One time when doing up a container I decided to add some leek butter to the pot along with the half and half and it was a big hit, so this time I added the leeks to the concentrate, more like a half cup. I'll likely still add the butter anyway as it help to richen the texture as well. The asparagus tips are still raw and crunchy so it helps to simmer it for a while to soften them up some if you want. Otherwise once the container is removed from the freezer and the base is placed in the pot still frozen and then the dairy added it's ready in about 15 minutes.