Adaptation from Nathan Myhrvold’s online version.
2 butternut squash, seeded, peeled, and cut into a coarse dice.
Half a stick of butter, cut into small pieces
1 tbsp of baking soda sprinkled on top of the squash
Heavy pinch of salt
Optional: 1 cup of water
Put into pressure cooker and get it up to steam for 20 minutes.
Blend and add either water or stock to think to desired consistency, balance the acid content with your choice (apple cider vinegar, red wine vinegar, lemon juice), and salt.
The depth of flavor in this soup is what impressed me the most about it, it’s trickier than it looks to get it to proper consistency. I finished it with Greek yogurt and sumac for color.
Any veg that benefits from browning would work. I’d imagine onions would work this way for a rustic french onion soup; the original version online had carrots. Too bad I don’t own a centrifuge. Yet.