I'm sure staples of the game are the apple pie, and roast chicken which sell for a whopping 8 gold when served to a customer, However when it comes to that profit margin the two stand alone.
Those 15 day goal bonus stoves that usually only have one recipe. Imagine if those gave a 8 gold serving, potentially at less than a 2 day cook time. It'd really make the 15 day goals worth chasing and more importantly it would add variety to the game.
for a long time the 15 day goals have been finished at a loss, I would be overjoyed to see something as exciting as a few new contenders stepping up to the 8 gold serving table. And I can't think of a better place to put it then behind a monumental achievement like the bi-monthly bonus goals.