In a large pot, or deep pan heat the olive oil, add the cauliflower, potatoes, and spices, pepper and sauté, browning the cauliflower a bit.
Add the tomato paste and 1 teaspoon salt, swirl it around heating it as well.
Add some hot water until cauliflower is about half way covered (you can always add more later if needed). Stir gently.
Lower heat, assemble cauliflower so that that stems face down. Cover pot and let it simmer for about 30-50 minutes (check that the cauliflower is very soft, but not falling apart, also the sauce should not be watery).
Serve warm or at room temperature, spoon some sauce on top and some feta cheese.