Preheat your oven to 350°Fahrenheit/175°Celsius. Grease and line an 8x8 baking pan, making sure that parchment paper is overhanging on the sides so you can easily lift the cake out.
In a large bowl, melt the butter. Let it cool slightly, then whisk in the sugar and two eggs. Whisk for 1 minute until smooth and slightly pale.
½ cup unsalted butter, ¾ cup white sugar, 2 large eggs
Whisk in the yogurt, vanilla extract and almond extract (if using).
¾ cup full fat yogurt, 1 teaspoon vanilla extract, ½ teaspoon almond extract
Fold in the flour, salt, baking powder, baking soda and cinnamon. Fold until there are no more streaks of flour!
1 ½ cups all purpose flour, ½ teaspoon kosher salt, 1 teaspoon baking powder, ¼ teaspoon baking soda, 1 teaspoon ground cinnamon
Pour the cake batter into the prepared pan, using a small offset spatula to even out the batter.
Sprinkle over your sliced plums. You can either arrange them in rows or drop them more organically (which is what I did!). Sprinkle over the slivered almonds and the extra tablespoon of sugar.
5 plums, ¼ cup slivered almonds, 1 tablespoon white sugar
Bake the cake in the preheated oven for 40-45 minutes. Allow the cake to cool completely before removing from the pan. It is a fragile cake so when you lift it do it gently!
Notes
My recipes have been developed and tested in cups and metric grams. I highly recommend using a weighing scale and measuring out your ingredients the metric way.I was inspired to add slivered almonds just before baking from the incredible "snacking cakes" cookbook by Yossy Arefi! 9" round pan: if you prefer you can use a 9" round pan instead of an 8x8, bake it for the same amount of time! Butter: I use European style butter, like Kerry Gold, in my recipes. This will make your finished bake much creamier and richer.Salt: If you don’t have kosher salt, halve the amount of salt called for in the recipe. 1 teaspoon kosher salt = ½ teaspoon fine salt. Please note I am using Diamond Crystal kosher salt and not coarse kosher salt (like Morton salt) which is far too salty for this recipe. Almond Extract: this is totally optional so feel free to leave it out if you aren't a fan of almonds! Storage: the plum cake can be stored in an airtight container in the fridge for up to 4 days.