Sneaky Spellcaster

Taking the time to really get to understand how you cast spells, you've noticed that not everything the books, or teachers, tell you is required. 

In fact, if you practice, you can make it seem like you weren't casting a spell at all. 

Taking this feat gives you proficiency in Sleight of Hand when casting spells. If you already have proficiency, or receive it from a different source, you gain expertise. But only while casting spells.