You know that cake baking is my passion, so of course, I wanted to make a cake with my plums as the star. However, I didn't want the cake to be too much effort eg cake plus filling plus streusel, as that meant I was facing the same issue as with the tart.
Google came to my rescue, and I found this recipe for Green Plum Dessert Cake on The Baking Brunette. There is a reason, I believe, why she doesn't have a photo of the whole cake - that is because it really doesn't look that pretty, as the top is all lumpy and bumpy. However, this should not put you off - this cake is delicious, as you can see from my photo of a cross-section of the cake. It is moist and reasonably light, and the slightly tart topping contrasts well with the sweetness of the cake.
The verdict - I loved this cake. It was easy to make, tasty, and fits in well with my adoration for green plums.