A delicious way to celebrate the new asparagus in spring, or broccoli in fall! Decadent, smooth, and satisfying - this soup freezes then reheats in the microwave *beautifully* - my favorite "brown-bag lunch" addition.
Melt butter & oil in heavy cooking pot, over med-high heat. Sauté onions and celery until tender (~4 min.). Add garlic and sauté ~30 seconds (don't scorch – gets bitter). Add flour, stirring constantly for 1 minute, to cook out raw flour taste. Add water, broth, and Knoor soup base (or substitute bouillon). Stir until smooth. Bring to a gentle boil. Boil for 2 minutes to set the thickening.
Add diced potatoes, chopped asparagus (or broccoli), salt, and pepper. Reduce heat to med-LOW and simmer for ~25 minutes.
Puree about ¾ of the soup in a blender in small batches. (Hot soup expands when blended, so fill blender only about 2/3 way full!). I place batches in an intermediary large Pyrex bowl to hold until returning to pot.
Return blended soup to pot. Stir in half-and-half, soy, and cheeses. Simmer (do NOT BOIL) 5-10 more minutes – stirring often, then taste for seasonings (probably needs a bit more pepper, doubtful it needs more salt – cheese, soup base, and broth are already somewhat salted).