I find it easier to cut entire categories of food. I don't do well with milk, so I rarely drink it, but never go near highly processed substitutes. I don't eat much meat or fish, so I base my meals around vegetables, not plants tortured into fake meat dishes.
Even so, I think it's always worthwhile to look for the best possible version of whatever we do still want to eat. Sure, we may be kidding ourselves a bit (or a lot) but it all helps move us in a healthier direction.
Ice cream. If you're not using the delicious homemade ice-cream recipes posted earlier 😍 then look at Haagen Dazs Vanilla. Cream, condensed milk, sugar, egg yolk, vanilla extract. That's it. Easy to add berries or lemon zest or grated dark chocolate. It's about the only widely available brand that has recognisable ingredients, and even then only in a few traditional flavours. Small local indies are often good too. Anything else, absolutely not (for me).
Peanut butter. Can be just ground peanuts (eg. Meridien), or peanuts/good quality oil/salt (eg. Whole Earth). OR it can have cheaper oil plus added sugar, stabilisers, etc (eg. Sun Pat, supermarket own brands).
Bread. Baked at home or in an artisan bakery, better; mass produced for supermarket with lots of added gunk, not.
Yoghurt. Traditional plain cultured milk, fine. Anything added, whether sweeteners or flavours or protein powder, not so much.
Breakfast cereals. For me, processed carbs are essentially a bowl of sugar, so I don't. I have oat groat porridge in winter. But if I had to have a cereal, then I might mix up a muesli based on oats, or, if it had to be a supermarket box, I think Shredded Wheat are the only thing that is just 100% wholegrain wheat, nothing added. Everything else has added sugars and is fortified to make up for the nutrients stripped in processing.
(Mostly I have a vegetables and eggs based breakfast/lunch - though eggs are tricky and expensive to find just now.)
The other thing I remind myself is just how much taste buds adjust over time! To the point where previously delicious foods taste sickly sweet or 'claggy' or 'dead'.
The trouble with everything I just wrote is that the best quality items are also the most expensive. So we're forced into carefully planned, highly selective food choices, and fewer calories overall. In truth, great for the health of most of us - but hell if you're trying to feed a family, most of whom aren't even on board in the first place.