Awesome pants by Lauren Riker. You can buy the pattern here for $5.
And if the photo didn't sell them to you then take a look at the blurb...
"Did you ever feel the urge to let everyone know how awesome you were, but you just weren't sure how to go about it? Did you ever feel like you needed some panties to put on when you were feeling sad, so you could feel awesome instead? Did you ever try to explain how awesome knitting is to someone, who just wasn't getting it? Well it’s your lucky day because these awesome panties have all your answers! Made with the super soft Microspun yarn, they are super comfortable to lounge around in, or to have as an extra layer in the Winter! This is Katie the model’s fave Girly Knits design, hope it’s yours too! Stay awesome!"