After Prince Philip and Princess Aurora/Briar Rose have met and done their little dance/duet, the way Prince Philip then asked "Who are you?", and in such a casual manner, is hilarious. Her reaction is even better. She sounds so surprised.
Every time Merryweather tries to get a piece of Maleficent, only for Flora to pull her back.
The following exchange between Flora and Fauna:
Fauna: [propping up a sagging 15-layer cake with a broom handle] Well, what do you think of it? Flora: Well, it's...it's a very unusual cake, isn't it? Fauna: Yes... [the cake frosting begins to flow down the broomstick, taking the lit candles with it, and Fauna scrambles to put them back on top] Of course, it'll be much stiffer after it's baked!
The blue-pink color fight between Flora and Merryweather, particularly when Maleficent's pet raven looks in the chimney to investigate the commotion and then gets shot in the face and the rear.
Plus the part after the aforementioned color fight when Aurora's dress gets turned into a Picasso.
Fauna:(reading recipe for a cake) "Two eggs, fold in gently." ...fold? [shrugs, then folds in two eggs— shell and all]
Her shocked expression when she hears the crunch really sells it. She knows something's wrong.
Fauna: Yeast, one tsp. [pronounces as "tisp"] Tsp?
The fairies attempt to make a dress, with Merryweather as the "dummy". It's all in Flora's deadpan delivery:
Merryweather: It looks awful. Flora: That's because it's on you, dear.
By the time Flora finishes the dress, it looks as short and plump as Merryweather instead of tall and thin, the sleeves have become too skinny for Merryweather to stick her arms into, and color-clashing pins and ribbons remain visible against the pink fabric. Merryweather looks utterly miserable while modeling it.
King Stefan and King Hubert having a drink. And then starting to have a brief argument (complete with Hubert using a fish as a weapon), which quickly dies and replace with laughter. During the scene, the minstrel sneaks a drink for himself a few times, and ends up drunk. By the end, he's passed out under the table, with his head stuck in the guitar. Try to keep a straight face as he snores in that thing!
After Hubert and Stefan's "fight" with the fish, Hubert sheathes it in his belt like a sword!
Apparently, in the search for Aurora, Maleficent's goons hunted for a baby for 16 years. Even Maleficent seemed to find it funny... at first.
When King Hubert sees Phillip and Aurora together at the end and gets so utterly confused, as he'd been told that his son was marrying a peasant girl. He eventually just goes with it.
Flora and Merryweather again fighting over the colour of the dress while Phillip and Aurora dance.
Flora: I do too... [gasps in horror] Blue! [waves her wand] Pink! Merryweather: [is happily enjoying the dance, then sees the dress is changed to pink and points her wand] Blue!
Even funnier, is how did Flora not notice the colour change before? Besides the fact that they were busy saving the kingdom...
The pink/blue war continues even after the camera "pulls back" to a still picture of Aurora and Phillip in a storybook.
This exchange between the fairies:
Merryweather: I'd like to turn her [Maleficent] into a fat ol' hop toad. Fauna: Now, dear, that isn't a very nice thing to say. Flora: Besides, we can't. You know our magic doesn't work that way. Fauna: It can only do good, dear, to bring joy and happiness. Merryweather:Well, that would make me happy.
Two words: "No carrots!"
When discussing Maleficent's seeming to know everything:
The German dub of the movie. Instead of a straightforward translation the scriptwriter opted for emphasising the "three bickering old ladies" aspect of the three fairies, partly through the choice of words, partly by adding additional lines spoken from the off. For example at one point Flora talks about Maleficent as if she is a woman of questionable reputation ("Ich kenn doch diese Sorte von Frau!"), and when Merryweather has to gather all her power for her gift, Fauna remarks from the off "Kräftig genug bist du ja." (Loosely translated: "After all, you are built sturdy enough for it."). Those little touches make the fairies just more hilarious.
Aurora's face when she realizes it's not the owl she's dancing with. To top it off is the owl's very sheepish shrug and embarrassed who-ing, as if he's giving an embarrassed chuckle.