Clean and separate 1 cauliflower into large flowerettes, cut the stem into small pieces. Put all in the pressure cooker. Add approx. 1 cup water. Cover and bring pressure up with high heat. When pressure is up, reduce heat and time 3 minutes NO MORE.
Remove from heat and reduce pressure immediately (can do this by running cold water over cooker if you don't have a steam release valve). Do not drain.
Return cooker to the hot burner, without the lid. Add 2 Tbsp. butter and about 2 cups milk - until cauliflower is almost covered, depends on size of cauliflower. Reduce heat to keep it from boiling. Heat until milk is scalded (a layer of scum forms on the top). Stir occasionally to keep it from scorching and to break up cauliflower. Add salt and pepper as desired.
NOTE: Sometimes I use Coconut or Almond milk. I don't use dairy milk often enough to keep it fresh.