There are 51 dishes in the game so you'll need to cook pretty much all of them. The recipes are acquired from quests so you should get them naturally as you do side quests. The last recipe book is from a citizen quest that can only be done in post game. Most ingredients are acquired normally although "melt-in-the-mouth meat" can only be acquired from the dragons around Ding Dong Dell. All item merchants from each town will have a single unique ingredient such as salt, broth, etc so be sure to stock up on them when you get the chance.