Diamond going on about how much effort she put into that cupcake. How she should be thankful she’d go so far as to make those cupcakes and let alone share them with some pony so unworthy of her sweat and baking skills, “Sharing is caring and I do so love to share. So eat up and marvel at my prowess in the kitchen.”
 
“Diamond…”
 
“Yes, Apple Bloom~?”
 
“The receipt on the box says Sugar Cube Corner.”
 
Diamond Tiara promptly shoves cupcake into the side Apple Bloom’s face.
 
“You and your silly observational skills, you always try and find something wrong whenever I grace you with kindness. It’s insulting, you know?”
 
Turns to see cupcake smeared over Apple Bloom’s face.
 
“Geez, Apple Bloom. Have some manners! Is that how you eat in public? That’s so uncouth.”
 
Diamond Tiara trots away to Silver Spoon after putting cupcake in Apple Bloom’s hoof.

@PonyPon  
See? Diamond’s not all bad. …She’s much worse. J/K

What a nice filly, sharing her cupcake.