Place oil in a medium saucepan, over medium heat. Saute onions until they are transparent, add garlic and cook for about 1 minute. Add the tomato paste, salt, and all of the spices to the pan and stir until the tomato paste is evenly distributed. Add brown sugar, vinegar, and crushed tomatoes. Stir to combine.
Let mixture simmer over low heat for about 45 minutes. Mixture will thicken to a ketchup consistency. Stir occasionally.
Wait till the ketchup is cool than use a blender to blend to the chunky ketchup smooth. If necessary strain the ketchup through a fine mesh strainer into a clean bowl. This will remove any unwanted seeds.
Taste and adjust seasoning as necessary. Store ketchup in glass jars in the fridge. Ketchup will last for up to 1 month in the fridge!