What a nice gesture to bake something for somebody when they are a little down. I totally can empathize with that As you said guava cake, I was reminded of the ‘guava cake’ from my childhood in Puerto Rico which was a jelly roll with a guava and cream cheese filling. I could eat it one in a sitting by myself if I was allowed. The jelly roll is called a Brazo Gitano- directly translated to Gypsy’s Arm, as in what the cross section of a gypsy’s arm would look like, with some imagination.
So I will preface this with- I HAVE NOT made this recipe. I did some simple searching and found what looked like the cake from before. I might try and make it though, now that I have found this recipe. It appears that the guava in use comes from guava jelly. This can usually be found in a hispanic grocer or hispanic food aisle, possibly one that sells pacific islander goods as well, though that is a less common cuisine in MN. Let us know if you find something more interesting.