Motor Design Decision

I am looking produce a small platform capable of rotating to discrete positions. The rotating plate is approximately 14" in diameter and needs to be able to rotate to multiple positions in 15 degree increments. I think a stepper motor would be the best approach although I am up to try whatever is most reasonable (possibly a servo motor). I have both analog and digital input/output available. The motor to turn the plate needs to be reasonably high torque to prevent mis-steps.

any suggestions on an initial approach?

How much torque? How fast?

How fast? Maybe 5 RPM at most. Honestly, the speed is almost irrelevant.

Torque? Well that is a little tougher. It looks like the plate has an inertia of 3.5oz-in-sec^2.

What are you trying to move with it?

Sounds like a stepper motor would work if the stepper position accuracy is good enough for you. A servo involves feedback which is significantly more complicated to implement. You need to look at the manufacturer's motor ratings for inertia loading to determine how big a motor is required to prevent mis-steps.

Or a solenoid, and rachet with pawl.