Line an 8x8 square pan with parchment paper. Cut a second piece of parchment paper slightly larger than pan base; set both aside.
In a large bowl, mix wet ingredients: peanut butter, honey, and vanilla extract.
Add dry ingredients, stirring thoroughly until mixture resembles cookie dough.
Transfer mixture to lined pan.
Press mixture evenly using extra parchment paper and the back of a measuring cup or glass, applying gentle pressure while moving in circles.
Refrigerate for at least one hour until set.
Using parchment paper handles, transfer to cutting board, keeping parchment underneath. Cut into granola bar-sized rectangles.