At some point, I heard that the opposite was true, ostensibly from a dentist on reddit. According to this anonymous stranger, after eating, your enamel is at its weakest, and you'll do the most damage to your teeth by brushing them. The reason was something about saliva and/or plaque that's been recently fed, I think.
(As a side note, some other dentist(?) in the same thread said that if you're going to brush your teeth once a day, it's most important to brush before going to bed.)
I don't really get it since my mouth tastes like mint for 30 minutes after brushing, which makes food taste gross.
That's the best time to brush. Otherwise, all the bacteria and the like in your mouth have all night to fester.
I also brush after breakfast, but this is kinda of common knowledge so I'm surprised you don't seem to know it.