Sometimes you just have to create a bit of a virtual reality, a Paleo re-enactment. Even if our food is no longer strictly Paleo, and even if there is no reason we should be very strict about every ingredient (see my post on epigenetic inheritance) food scarcity was more common than food abundance, even in the Neolithic. This might have to be seasonal, to allow for regeneration and repair, but should be considered critical. If CR and longevity is the only goal, food scarcity would be even more important.
When food is everywhere we are tempted and temptation is bad. When we see food and conceptualise eating eat, even if we forgo the opportunity, the brain still registers food, with all biochemical consequences to follow. Just looking at food elicits conditioned responses, which can confuse out metabolism.
But what can we do not to be led into temptation? I think there is a solution: you have to reprogramme you brain, so that is does not perceive most available foods as edible. You simply have to visualise the unhealthfulness of those foods, even possible toxicity, to develop avoidance reaction. Obviously you already have the right reflexes when subjected to the risk of eating a cake or pasta, but some Paleo-like foods are still tempting.
Here are some suggestions to make these associations:
Nut butter from the jar: roasted (AGE compounds - bad), processed fats, possibly in high temperature (possibly trans-fats). Of course you could make your own healthier version, but have no time, don't want to bother, are not that hungry after all. Result: you wait till you have your salad and steak.
Processed meats: nitrates, oxidised cholesterol, contact with plastic packaging; this is clearly not edible food. It surely might be tasty, but it is not food. Making your own would be too much trouble and you go for the leg of lamb instead.
Honey: find an obscure kind of raw honey which you can buy only at a far away farmers market and only twice a year. Any other honey would be just not good enough or contaminated with toxic pesticides. When you buy this honey, eat the while jar to make your head spin, so that you condition yourself to avid for a while. Visualise glycation and its contribution to wrinkles and infertility.
Chocolate: It may be 91% cocoa solids, or even 100% when you mix cocoa liqueur with cocoa butter, but this is not Paleo and should not be in your kitchen in the first place (it is in mine though). If you can't resist, at least don't add Stevia to it; Stevia is a highly processed extract, which will mess with your insulin and digestive juices through conditioned reflexes. Want a treat: eat some raw coconut, if you can find it at home.
Which brings us to another strategy: not to store food. Fresh food is always better, even freezing increases oxidation of fats. Don't cook too much, fried leftovers can be tasty, but are less healthy and should be avoided. Visualise toxicity.
If cheese or cream is your weakness, there is no remedy. If you consider it "approved", then it would be hard to condition your brain to see it as toxic.
After a bit of training you will be able to walk into a supermarket and see no food there. That restaurants do not offer any food you have already discovered a while ago...