the best actors at playing stoic characters

Anthony Hopkins
Clint Eastwood
Dakota Fanning
Kevin Costner
Liam Neeson

Morgan Freeman
James Earl Jones
Robert Mitchum

Buster Keaton

Edward James Olmos - Lt. Castillo in the tv series Miami Vice, a gang leader in American Me and most recently this: https://moviechat.org/tt0271022/The-Judge. He played significantly different characters but in the same style, where stoicism was definitely an obvious trait but with subtle variations in each performance.

Adam Sandler

Jeff Bridges
Josh Brolin

Gary Oldman
Ed Harris
Morgan Freeman

Viggo Mortensen