I heard if you perfectly shuffle a deck of cards 8 times, it returns to it’s initial order. You could set the ace through king up before hand, perfect shuffle it 5 or so times, show the deck to be random, and complete the 8 by shuffling it for the spectator. The spectator could not shuffle it before hand, but at least it looks shuffled to them at first. Not sure if that’s what you’re looking for, and you would have to learn the perfect shuffle, but that’s the only way I can think of doing it.