making brownies

Sometimes, it's awfully hard simply to decide whether to use the 8x8 or the 13x9 pan.

{
+ If I use the big pan, it'll look like I have more brownies!
- But they'll be thinner and might over-bake and end up hard/tough.
- The big pan will take more space in the fridge.
+ If I use the small pan, the brownies will be nice and thick.
* Mom always made brownies in a 13x9 pan when I was a kid, and they were good and chewy even though they were thinner.
- But I was a kid; small things seemed bigger back then than they do now.
* Maybe I should make both boxes of brownies at once, in the big pan?
... 13x9=117. 8x8=64. 2x64=128. Using 2 boxes in the big pan would make even thicker brownies than using one box in the 8x8 pan. They might not get cooked enough in the center; I'd better not try that.
* Maybe I ought to do something with the yellow cake mix at the same time. Yellow cake + brownie swirly thingy? 1 package of cake mix requires the 13x9 pan. If I mix them, I'd have to use only half of the cake mix or it might overflow the pan. I suppose I should stick with just brownies for now.
... So, which pan should I use?
}