This looks like a pan that was popular with a box cake back in the 70s, and I can’t recall the name of the pan or cake, LOL. You made the box mix, and filled the indentation with a creamy type mousse, and topped with canned pie filling. I recall the chocolate cake mix, chocolate mousse filling and canned cherry pie filling. All these things came in the one box mix.
Now that I know how to bake, hee hee, I wonder how we ever ate that stuff.
You could bake a yellow cake in it, and fill with strawberries and whipped cream at this time of the year.