Wash the celeriac and place it on the cutting board.
Cut the top off and slice the celeriac into wedges. Peel the wedges.
I had about 12 ounces of peeled celeriac. You can use more or less celeriac. It doesn't matter a whole lot because you will adjust the liquid later.
Wash the wedges off and place them into a pressure cooker or a pot on the stove. I use my Instant Pot!
Add 2 cups of water.
Set the Instant Pot to "manual" and "25 minutes". Or cook on the stove until tender, adding more water if needed.
Allow a natural release for 5 minutes. Then do a quick release.
Spoon the celeriac into a blender. Add most of the water, the salt and a heaping spoonful of love. Blend, adding more water if desired for the thickness you want. Or blend with an immersion blender.
Taste, adjust seasoning. Enjoy!
Celeriac is not listed on the SIGHI Food Compatibility List. It is not on any list as being high in histamine, but that could be because it is an odd enough vegetable that it wasn't considered. I seem to do fine with it. Test it carefully if you are unsure whether or not it will work for you.
I live at 7000 feet so my pressure cooking times are longer. If you live at a lower altitude then try cooking for 15-17 minutes. You need the celeriac to be really tender so it will blend smoothly.