- In a large pot or deep skillet, heat some oil over medium heat. Add the onion and sauté until translucent, about 5 minutes. Add the garlic and ginger and cook for another 1-2 minutes. 
- Stir in the tikka masala paste, turmeric, cumin, coriander, paprika, cinnamon, and salt. Cook for a minute to toast the spices. 
- Add the sweet potatoes and chickpeas to the pot, stirring to coat them in the spice mixture. 
- Pour in the diced tomatoes, vegetable broth, tomato paste, and coconut milk. Mix everything together well. 
- Bring the mixture to a boil, then reduce the heat and simmer for 20-25 minutes, or until the sweet potatoes are tender. 
- Taste and adjust the seasonings if needed. 
-  Serve the tikka masala over cooked basmati rice, garnished with fresh cilantro.