One of the best ways to increase the odds of finding and catching Shiny Pokémon in Pokémon Scarlet and Violet is by making Sparkling Power Sandwiches which, when consumed, have a boost that does exactly that.
There are 18 available, all of which have different recipes.
Since most seem to contain a key ingredient, Herba Mystica, which comes in five different forms, including Bitter Herba Mystica, Salty Herba Mystica, Spicy Herba Mystica, Sour Herba Mystica, and Sweet Herba Mystica, it begs the question: are there any that don’t actually require Herba Mystica to make in Scarlet and Violet?
Simply put, the answer is no. All 18 Sparkling Power Sandwich recipes require either two lots of one specific Herba Mystica, or a combination of two different ones.
The good news, however, is Herba Mystica is relatively easy to obtain—assuming you’ve reached the endgame and unlocked the ability to do Five-Star Raids and Six-Star Raids.
If you haven’t reached that point but still want to increase the odds of catching Shiny Pokémon, instead of using Sparkling Power Sandwiches, you can use the Shiny Charm or look for them during Mass Outbreaks, which crop up in various zones on the map from time to time.
It might take a little longer, but it’s better than nothing. Plus, when combined with Sparkling Power Sandwiches once you’ve acquired some Herba Mystica, it will increase the odds of even more.