Here are some improved, more natural versions of your caption:
Clean recipe style:
Pour condensed cream of chicken soup over raw sliced russet potatoes, add one extra ingredient, and bake in a glass casserole dish for a simple, comforting meal.
Smoother viral style:
Raw sliced russet potatoes, condensed cream of chicken soup, and just one more ingredient—baked together into a cozy, comforting casserole everyone loves.
Short punchy hook:
Just potatoes, cream of chicken soup, and one extra ingredient—baked into the easiest comforting casserole.
If you want, I can also turn it into a full step-by-step recipe or make it more “viral Facebook food post” style.