Peel and dice the yellow onion, ginger, and garlic.
Add olive oil to a large frying pan or sauce pan and add the diced onion to it. Place pan on a stove top set at medium heat and saute onion for about 5 minutes. Make sure to stir a couple of times so it doesn't burn.
Then add in the garlic and ginger to it and saute another 5 minutes, stirring as needed.
As onion, garlic, and ginger are sauteing, peel the extra leaves off the cauliflower head. If there are brown spots on it, slice those parts off and cut the cauliflower head into bite sized florets.*
After sauteing the onion, garlic, and ginger, add in the coriander, smoked paprika, turmeric, cumin, and (if using), chili powder, coconut milk, water, and pumpkin puree and stir well until all ingredients are well incorporated.
Then add in the cauliflower florets and stir into sauce. Cover with a lid and let simmer for 10 minutes covered.
Remove lid, add in cilantro, season with salt and pepper to taste and enjoy warm.