Wow, these things are good. I found the recipe on Wee Eats, however, I think she must be from the UK because all the ingredient measurements were strange. So here is the recipe in "normal" (at least for me!), also with an amazing epiphany suggestion: these were amazing, but I think they could be even amazing-er with some type of canned pie filling over the top. As I was eating it, I was enjoying the rich gooey butteriness and thinking, "This would be awesome with cherries." So, just my two cents. But they are ridiculously good just plain, too.
Ooey-Gooey Butter Bars
A yellow cake mix
1 stick butter, melted
8oz. cream cheese, softened
3 1/2 C powdered sugar
1 tsp vanilla
Preheat oven to 350F and line an 8x8 inch pan with parchment paper. First, you're going to make the 'bar' part: mix the cake mix, 1 egg, and butter. Press the dough into the pan evenly. Now, you're gonna make the 'ooey-gooey' part: Cream together the cream cheese, 2 eggs, sugar, and vanilla. Pour over the the bar layer. Bake 45 minutes or until edges are golden brown and center is creamy, yet firm (like cheesecake). Cool completely, put it into the fridge, then cut it into squares. Store in the fridge - not only because it's cheese, but also because they get a little messy when warm. FYI, they are super rich... yay! :)
(You can cut the corners on the paper to make it fit better)
(this is the ooey-gooey part...)
(and... the finished product!)
And, as always, enjoy!