Saute onions in a pan with olive oil, over a medium/low flame. Stir often to make sure onions are caramelized and not burned. Keep on stirring occasionally and cooking onions for about 20-25 minutes.
Add ginger and garlic and saute about a minute or so.
Then add in tomato paste, fire roasted tomatoes, coconut milk, smoked paprika, chili, coriander, cumin, turmeric and water and stir till well incorporated.
Then add in cauliflower and carrots and let simmer covered about 10 minutes.
Add in the green bell pepper and let simmer covered again for another 5 minutes or till cauliflower is tender.
Then add in the yogurt, season with salt and pepper and enjoy with naan or rice! *Can be served with a dollop of Greek yogurt and green chillies if desired.