I enjoy making my own sourdough bread, smoked meat, growing veggies, and such. Doing these DIY saves money and is fun, but is somewhat involved and can be time consuming. These are more like hobbies than generally applicable ideas.
However, I'm noticing that there are simple little things we buy in the store that are unnecessary and don't really save time, and are often inferior to home made versions.
For example: Balsamic vinaigrette dressing. No need to buy from the store, super easy to make from already in the cupboard. Two parts olive oil, one part balsamic, salt, pepper. Shake in small mason jar. Done! Use a good oil and vinaigrette and you have way better than what you usually buy. Less stuff to buy and keep stocked.
Another example: Taco/fajita seasoning. We used to buy the seasoning packets, but they are full of a bunch of preservatives and anti caking stuff. Again, super easy to make with spices already on hand -- chili powder, cumin, onion powder, cayenne, salt, pepper. Tastes better. Healthier. One less thing to buy and stock in the house.
Final example: Pancake mix. We don't make pancakes very often because they're not very healthy. Our store bought pancake mix would often expire before using it all, and it took up space in the cupboard. Surprising how easy and quick it is to make it from scratch from staples we already stock: butter, eggs, all purpose flour, milk, baking powder, salt. And tastes way better.
I think we were buying a lot of these things from the grocery store just because that's what we knew growing up. So I'm wondering now, what other things do people find are quick and easy to make from scratch from staple ingredients rather than buying special purpose?