Can I cast Mind Sliver before a Quickened spell to give the malus to the saving throw? [duplicate]

Question

I am currently building a Aberrant Sorcerer heavily relying on Spells that involve Enemy Saving-Throws. I already planned for the use of Silvery Barbs to reduce the chance of Enemies succeeding very important Saves.

Casting Time: 1 reaction, which you take when a creature you can see within 60 feet of yourself succeeds on an attack roll, an ability check, or a saving throw

You magically distract the triggering creature and turn its momentary uncertainty into encouragement for another creature. The triggering creature must reroll the d20 and use the lower roll. [...]

— Silvery Barbs, Strixhaven: A Curriculum of Chaos, pg. 38

When looking at my Subclass-Spells I found out that Mind Sliver might be another way for me to decrease the success rate for Saving Trows.

You drive a disorienting spike of psychic energy into the mind of one creature you can see within range. The target must succeed on an Intelligence saving throw or take 1d6 psychic damage and subtract 1d4 f from the next saving throw it makes before the end of your next turn.

— Mind Sliver, Tasha’s Cauldron of Everything, pg. 108

Now for my Question: I know that I can use a spell as a bonus action using Quickened Spell followed by an Action Cantrip. While I might not be able to use my reaction to cast a spell in the same turn I wanted know whether it is possible to cast the action Cantrip first (Mind Sliver for the -1d4 to Saves) and then use a Quickened leveled-Spell relying on low Saving Throws?

I think this might be quite useful / can be helpful when dealing with GM's banning Silvery Barbs

Answer 1

Yes, this is perfectly legal. Your Action, Move, Object Interaction, and Bonus Action can happen in any order you desire on your turn, assuming something else (such as a foe's Reaction) does not occur to stop your intended sequence.

From the Basic Rules, Chapter 9, under "Bonus Actions":

You choose when to take a bonus action during your turn, unless the bonus action's timing is specified, and anything that deprives you of your ability to take actions also prevents you from taking a bonus action.