Having another look at the bills and trying to trim something off groceries. I do a lot of cooking from scratch already. I have chickens so the little food waste we have comes back to me in the form of eggs :)
Stuff that I do think is cheaper to make; pizza so long as you use cheapie mozzarella balls and not pre grated stuff. Pasta sauces. Soup.On balance it's cheaper to make your own meatballs/ burgers as you could buy them cheaper but the meat is so poor you lose a third to melting fat.
Anything pudding based it's often cheaper to buy from supermarkets. I made an apple and blueberry strudel yesterday and even although the fruit was free the cost of the ingredients was probably more/ the same as a frozen one from the supermarket. Cakes/ biscuits are very cheap premade.
I make my own jam with free/ cheap fruit but the cost of the sugar is more than the cheapest jam at the supermarket. I can make bread but at double the cost of a loaf of cheap white from the supermarket. It's not really a fair comparison because if you're trying to get your shopping bill down it's probably not awash with artisanal loaves.
I do wonder if I'm missing something though, so would love to hear what it is you make from scratch that's cheaper than premade.