You tell her to use her power to have full control of her powers

You point her towards the most obvious solution, that she just use her power to make herself be fully in control.

You say:

"Jane just use your power."

Jane replies:

"What do you mean?"

You continue:

"Close your eye´s, just imagine yourself fully in control, having fully mastered your powers and make it reality!"

Jane follows your instruction, but you can see that she´s obviously struggling with it as she clenches her eye´s, you say warmly:

"Just relax, I believe in you, Jane you are amazing, you can do anything you want, you always could, you were just so hard on yourself all this time. Even when we were young, I could see it, you always could do anything you set your mind to, the only problem was your self doubt. But I always saw how hard you tried and you always ended up doing what you wanted to do, just like now, I can see it, you just need to believe it yourself, when you do, you can do anything, it´s one of the reasons I fell in love with you!"

Jane relaxes her closed eye´s, for a second, lets out a slight breath and you suddenly feel like everything has shifted, you can´t put your finger on it, you half expected some kind of over the top power up, but it doesn't happen. Then she opens her eyes and looks at you...

Her eyes shine in an ethereal color giving off endless dept and power, you suddenly feel so small, before an endless power, but Jane blinks and suddenly her eye´s are her own color again.

She smiles at you warmly and sheepishly for a second as you just sense your old friend again, the woman you love.

You and Jane just stand looking at each other, until you say:

"So what now?"