This is like a cherry cobbler (Jerry calls it "cherry gobbler"). It's a favorite dessert at our office parties. I made it for Christmas dessert last year (2002) and got the following comments: "This is better than [country music star] Tim McGraw!"; "This is better than chocolate!"; "This is the best dessert I've ever had!" I think they liked it!
Lightly spray 9 x 13 pan (preferably glass) with Pam (or a light coating of other vegetable oil).
Spread crushed pineapple and cherry pie filling in bottom of pan, gently stirring to mix evenly.
Sprinkle cake mix in an even layer on top; gently "level" with hand, taking care not to poke into fruit layer.
Sprinkle nuts evenly over the top of the cake.
Slice the butter into very thin slices (this works best when the butter is very cold). Place butter evenly over entire top of cake, covering as much of the surface as possible. (NOTE: You may need a little more than one stick of butter, depending on the size of the pan you use.)
Bake at 350F for 45-55 minutes, until top is lightly browned and fruit is bubbling.
May be served warm or cold, but it's best served warm with vanilla ice cream.