Slice the onions and cook in 1/4 stick butter until soft and light brown. Remove and set aside. Slice the cube steak against the grain. Sprinkle with seasoning salt. Heat 2 tablespoons butter over high heat (in same skillet) until melted and beginning to brown. Add the meat in a single layer. Cook one side until brown, and then flip and cook until brown, about a minute on both sides. Add 1/2 cup (at least) Worcestershire sauce, 5 to 6 shakes hot sauce and 2 tablespoons butter. Add the cooked onions. Stir to combine. Butter the halved French Rolls and brown in a skillet. To assemble, lay the bottom half of a French Roll on a plate. Place the meat mixture, followed by a spoonful of juice from the pan. Top with other half of roll and cut in half.