The constraint is always raw material. She has no shortage of ideas or time in which to put them into practice. Hence, she is most avaricious in acquiring hearts whenever an opportunity presents itself. Having a stockpile means she need waste as little time as possible.
She points to one. "That one's close-ish, and they've got healthier animals, I think, and they don't mind me too much."
"Alright!"
And she leads the way, scampering to the edge of the village to steal their eggs - quite a few - and then back out a distance, where she finds a comfortable pair of rocks to perch on.
"So! Try to focus on wanting these hard-boiled - just one at a time, mind you, whichever you're holding." And she offers one up.
She takes it. And starts to focus.
It has been a while since she's eaten. She's hungry. Can't eat the egg raw, though. And there's no other way to get it cooked here.
Well, it should hurry up. This is magic, it's ridiculous that she has to wait. She wants this egg to be hardboiled right now.
Yet another grievance to add to this day's list of sins. Hurry up, dammit.
Her hand tightens too much on the egg, and it cracks apart.
It's maybe a bit firmer than it should be raw, at least.
The girl hands her another egg.
Jaw clenched, she wipes her hand off on the grass and prepares to try again.
For some reason, it goes a bit easier this time - but not quite perfect. The yolk's still a bit runny.
She cracks the shell and peels it off, then eats the egg. She is hungry, after all.
The girl grins. "You should also boil the rest, to practice it."
Om nom nom!
"So what're you hoping to do with your magic?"