(okay, I kinda stole this from Bakerella, but I did change it from peaches to pears, since I don't like peaches!)
2 15oz cans sliced pears in syrup (or peaches, I guess)
1 box yellow cake mix
1 stick butter
1 cup loosely packed brown sugar
1/2 cup chopped walnuts
Dump the fruit into the bottom of a 9x13 pan, syrup too. I cut the slices into chunks, 'cause bakerella said to, and I honestly thought it would be easier to eat. Spread the dry cake mix directly over the top of the pears (nope, don't follow any of the directions on the cake mix box). Cut the stick of butter into pats and place evenly on top of the cake mix. Spead the brown sugar over everything. And then sprinkle the nuts on top.
Bake in a 350 degree oven for about 40 minutes.
(after 40 minutes, mine still seemed runny, so I took a fork and kinda mixed everything up a bit. Then I stuck it back in the oven for maybe 10 more minutes).