I dunno but was at a fall fest over the weekend and one of the girls brought homemade snickers bars "bars", beyond amazing, seriously....said she found the recipe on pinterest (you might be able to search for what you're looking for there) I'm afraid to look, would be tempted to make homemade chocolate bars, that can't be a good thing
I'm on my phone and can't link right now, but Brown Eyes Baker's (a blog) chunky pecan pie bars are awesome.
If you google the blog name with the recipe it's on the first page. Sorry for no link.
ETA: it says to let them cool completely because the chocolate and filling are all gooey when they're warm, but I never wait. I let them cook down until they're mostly set, but the chocolate is still kinda melted.