Just a quick heads up before blizzard change it.

At some point when you cook (770-800) everything becomes either grey or green, meaning its hard to get skill lvl, but there is a daily cooking guy in Ogrimmar from way back in the days that give you a quest that gives +1 cooking skill
Marogg - NPC - World of Warcraft

hope it helps for people that want skill lvl 800! enjoy

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