Add olive oil over medium-high heat in a medium, heavy-bottom pot. Add the onions and saute for about 5 minutes until translucent. Add spices, stir for a few minutes to allow all the flavors of the spices to come out. Add all the remaining ingredients, stir well to make sure every piece of cauliflower is coated wit the sauce.
Put the lid on the pot, cook on low for 20 to 30 minutes on low until the gulpea can be easily pierced by a fork, stirring every 5 minutes. The gulpea has enough moisture so the bottom doesn’t burn, but if you find the sauce is drying up and you need a little more liquid, either add 2-3 tablespoons of water, vegetable broth or olive oil. If your gulpea is too watery, remove the lid and cook uncovered for another 5 minutes to allow the sauce to reduce. The cooking time will vary but you want the result to be fork-tender, but not mushy.
Serve with nan, pita bread, or challaw, the Afghan white rice. A dollop of plain yogurt makes a heavenly addition.