I have dinner with my family generally once per week, and they quite like tacos. I actually took the taco mix packet to the spice section, and bought all the different spices that were listed on the taco mix packet, and a bottle of passata (there's an italian brand I like which is only about 1% sugar), and then put the taco mix back. Cooked up the mince, didn't measure anything, just chucked the spices in. My brother likes to put refried beans in the mince, which makes it nice and thick, but contains barely any sugar. Literally tasted just like normal taco mince, and took no longer to cook than regular taco mix.
One thing I have learnt that often times it's just as quick and easy to make something from scratch as it is to buy prepackaged mixes, and it's good because its often fresher, tastes better and you know whats in it. Plus once you have the ingredients, you can make it again.
As for tin tomatoes, I've bought Annalisa italian diced tomatoes for ages, it's 3% sugar, and only contains tomatoes and tomato juice. Its the only one I've been able to find that doesn't have excess ingredients and preservatives added to it.
