Strain the liquid tomato through a coarse strainer to separate seeds and skin from raw tomato puree.
For tomato paste
In thick bottomed and wide pan, take tomato puree, sugar salt and bay leaf. Cook on high heat for about 45 minutes.
Cook further on medium flame for 20-30 minute with occasional stirring. Remove bay leaves and discard.
When tomato puree is thickened to a paste like consistency cook on slow to medium heat until water doesn't separate from the sides of paste. (That's the sign of completion.)
Notes
Spoon the paste into ice cube tray and freeze. Once frozen store in freezer bag and use as required.