SSS won't work with single-sided geometry as it needs a volume, but single-sided meshes are useful for foliage, feathers and dynamic cloth among others. Here are a couple of ways to add more options to those kind of meshes using the Principled BSDF with other Cycles nodes.

First, the Geometry node can be used as a mask to put a different material on the back-facing geometry. I made a simple ring, had the same setup as above on the Ground, used a single area light in front of the mesh, and set up this -

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