I made this block using scraps today from a pattern I found on a blog called Lily's Quilts, which you can find here. The blog's author, Lynne, made her block with a black background, and was more artful about how she arranged the pieces, so that she ended up with a block where the two overlapping squares embedded in the pattern emerged more clearly. If I make this block again, I'll try to follow her example more closely, so that my block won't look like such a jumble of color.
She wasn't sure whether she'd invented the block, or what it's name was, so she decided to name it after herself.....and one of my favorite cartoon characters: LynneBob Square Pants. I've abbreviated mine to be called simple The Square Pants Block..