First thing you'll need is a broken powder compact. Mine is hoola bronzer by Benefit. You can do this with blush, bronzers, eye shadows, etc!
Pour in some rubbing alcohol until its all absorbed. Start with small amounts depending on how much powder you have.
After you add the alcohol mix it around with your finger.
It should look paste-like...like this
Flatten it out as best you can and leave it overnight!! All the alcohol will evaporate and you won't have to buy new makeup!
This was taken about an hour later. You can tell the alcohol is evaporating already and the color is much lighter and almost back to normal!
The mac studio fix the next day! Alcohol smell is completely gone and it swatches the exact same as before. I guess I could have done a neater job flattening it and making it level but that's okay.
There's the hoola bronzer after the alcohol evaporated! Works just the same!