And the evidence that one tasleem is sufficient, and this is from the differences in what is permissible, so the one who is praying has the choice between giving one tasleem or giving two tasleems, as is the view of the people of Hijaz.
It is narrated from Sayyidah Aisha (may Allah be pleased with her) that the Prophet Muhammad (peace and blessings be upon him), while in prayer, would incline slightly to his right side and turn his face (i.e., forward) to give the greeting of peace (salaam).