[SIZE="4"]First Step - Get Ready for the Dungeon[/SIZE]
Before entering the dungeon, get ready everything you think might need.
Useful Items:
Potions - Keep your health/stamina and even mana up. Personally, after using transformation, hp 30's are enough for me for the rest of the run.
Armor - Deduces damage.
Weapons - To kill things.
A shield - To go with the cooking knife you will pick up within the dungeon.
Useful Skills:
Smash - This is a good skill to kill those giant ingredients at first, as well as for the silverware and the rat.
Windmill - Crowd control.
Evade - The ingredients tend to shoot the magic bolts as soon as they finish loading them, so if you time it right you could dodge it and save the knockback/stun time.
Mana Shield - This is great if you have a decent mana pool. Saves a lot of hp potion usage.
Transformation - Makes this dungeon a breeze.
[SIZE="4"]Second Step - Get to the Dungeon[/SIZE]
Go into Tara castle (west of Taillteann/Emain Macha) and enter the first floor. Go to the word 'Kitchen' on the mini map. Talk to Glewyas and purchase a recipe (they restock every 12am in-game time) and click the iron pot to enter.
[SIZE="4"]Third Step - Killing in the Dungeon[/SIZE]
All of the ingredients in this dungeon have extremely high protection. To lower it, you will either need to wait until Glewyas hits them, or kill the silverware that spawns for your own protection-lowering cooking knife. The rat and silverware do not have high protection. The ingredients also have to die within the red circle for it to be counted for the recipe.
If you click the Info button next to the Exit button at the top right of the screen when you enter, you can see how many ingredients you have to kill in how long. The timer starts the moment you enter, so you should hit the orb as fast as possible. To end the dungeon, you have to hit the big wooden fork. Even if you do not have enough ingredients when the time is up, hit the fork anyways, because the time that the recipe has been cooked for is a lot more important than how many ingredients you have killed.
When you hit the orb, Glewyas will spawn, as well as the ingredients. Have your weapons equipped (shield sheathed), and let Glewyas hit the ingredients 4~5 times. After that, race to kill 2 ingredients (Having Smash load while Glewyas does the opening hits here could help). I have found that the silverware always spawn after the second ingredient is killed.
Focus on killing the silverware once it spawns, because it will drop a cooking knife you could use to lower the protection of the ingredients yourself. The silverware will not attack you, unless if you windmill it in defense or attack it directly (although sometimes it doesn't even aggro me when I smash it). To do this, I like to windmill it a few times and then smash. Keep in mind that the silverware will hit you for a lot of damage, if it aggros you.
Once you equip the cooking knife, you can start whacking the ingredients yourself. Turn on mana shield if you wish. If you need to windmill, turn off mana shield while you load your windmill so it doesn't take 10% of your mana as well. I like to use transformation right after I get my own knife, because then I have enough attack power to normal hit the ingredients to death with only using the cooking knife, and saves my hp that would have been lost to windmilling.
Rats - They occasionally spawn, and you have to kill them outside the red circle. If you don't you lose a lot of points for your dish. One way to dispose of it is to use the cooking knife to hit the ingredients close to it. The damage will splash, and the rat will have one '!' sign above its head. However, it will not aggro you, and just circle you (Assuming you did not splash it when it had defense up). Once it wanders to the outer edge of the red circle, beat it to death. They do not have to be killed them immediately, you are fine just as so they do not get into the pot. You can even hit the fork to end the game even if there are still rats on the field.
Silverware - You can kill them anywhere you want; they do not deduct points from your score. Additional silverware might spawn over the course of the run, but I prefer them dead because they take up precious food spawn slots (same with rats).
Extra - Beware of Glewyas, he is evil. Sometimes at the start he maybe smash or even worse, load windmill against the ingredients. When that happens, he could stand in that same spot for quite some time, so it would be better to just restart the dungeon. Also be careful of him when you are trying to dispose of the rats, his splash damage could screw up your combo, and the rat might die within the red area. Then he blames it on you.
[SIZE="4"]
Fourth Step - Rewards of the Dungeon[/SIZE]
Go check the wiki.