stared

[carat]

Are both sentences possible? If so, what does the continous form express?
She stared at herself in the mirror.
She was starring at herself in the mirror.

 

[emsr2d2]

Are both sentences possible? If so, what does the continuous form express?

She stared at herself in the mirror.
She was staring at herself in the mirror.

Yes, they are both possible. There's little to choose between them given that they both refer to the past. They could convey different meanings but that would depend on the surrounding sentences and the context (as always).