Casting plaster figurines


So I'm hoping to start doing some casting of plaster figurines soon, but this will be my first venture into any sort of molding/casting in like 20 years, and my first ever adventure with plaster casting at all, so...

What is the preferred method for molding and casting plaster figurines (say, about 11.5" x 3" x 3"? I was thinking of two-piece molding it in silicone, but I wasn't sure whether solid block backed with resin or shell mold with a resin mother mold would be better, or if there's another, better way? I would want to be able to make many many plaster casts from this mold, so it need to be quality materials.

I've followed a lot of mold-making threads on here, but largely they are for larger pieces like helmets, busts, and props, and almost none would be in plaster, so I thought I'd just see what sort of experience folks have had. Thanks!