Okay, after many attempts, I got through this. The quality of the cooking result does matter. If you got a result 'better not show this to anyone' but it's a sell's worth of 6, then you cannot bribe the dog with it.
Ah, wait—if what you ended up with is a piece of shit on a plate, then of course he’s not going to eat it XD
By the way, I’ve made a patch that fixes Easy Mode, so it now works properly. You can download it directly from the game’s page.
Thanks! And for the record; I do not hate puzzels, I like them for the variety, but I'm certainly not good at all of them. ;-)