What is the best and fastest way to cure frozen shoulder?

Runs its course..... Adhesive capsulitis (frozen shoulder) runs its course through a "freeze-thaw" sequence. It does get better over time, but it can last over a year. It is painful and can impact your sleep. You can try measures like anti-inflammatory over-the-counter meds, heat/cold, physical therapy. If you can't wait this out, you might want to ask your orthopedist about shoulder manipulation under anesthesia.
Frozen shoulder. There typically there is no quick fix. Often times the shoulder needs to run its course (which can take months). I have seen people benefit from cortisone injection into the glenohumeral joint in clinic. I have also found stretching the shoulder to the point of pain but not through pain with heat before and ice after can help minimize inflammation and post activity swelling/discomfort.