Heat oil in a large skillet over medium heat. Add cumin seeds, cinnamon stick and bay leaf. Sauté for 30-45 seconds.
Add the finely diced onion and quarter teaspoon of salt. Cook for 5 minutes, do not brown. Add the finely chopped serrano pepper ( or green chili), ginger, garlic and turmeric and saute for one minute.
Add Kashmiri red chili powder, coriander powder, cumin powder and tomato paste. Cook for 45 seconds. If you feel the spices are burning add little water.
Add the tomato sauce ( or the pureed tomato) and sugar and cook for 7-8 minutes till tomato starts leaving the side of the pan.
Add butter, garam masala and kasuri methi ( fenugreek leaves). Lightly crush the fenugreek leaves before adding. Stir and cook for one minutes.
Add cream and water and mix it well. Check for seasoning and adjust the salt or spices. Simmer for couple of minutes till you can see some bubbles.
Add the cooked and drained pasta and cook for a minute.
Finely add some chopped coriander and lemon juice (optional). Serve the tikka masala pasta warm.