Method

• Preheat the oven to 180C Butter a 20cm square pan, dust with flour, tap out excess
• Sift the flour, baking powder, cardamom or cinnamon if using together
• Using a electric mixer, beat the butter at medium speed until it is creamy and soft
• Add the sugar and beat for 3 minutes, then add the eggs one at a time, and beat well between each egg
• Still working on medium speed beat in the oil, zest and vanilla; the batter will look smooth and creamy, almost satiny
• Reduce the mixer speed to low and add the dry ingredients, mixing only until they are incorporated
• Run a spatula around the bowl and under the batter, just to make sure there are no dry spots, then scrape the batter into the pan and smooth the top
• Arrange the plums cut side up in the batter– four rows of plum halves each – jiggling the plums a tad just so they settle comfortably into the batter
• Bake for about 30 minutes or until the top is honey/golden brown in colour and puffed around the plums, and if inserted with a skewer it will come out clean
• Transfer the cake to a rack and cool for 15 minutes during which time the plum juices will seep back into the cake then run a knife around the sides of the pan, invert and cool right side up
• Once cool, I dusted mine with icing sugar
• It soaks into the plums, but keeps the cake a speckly white
• You can wrap the cake and keep it at room temperature for up to 2 days, during which time it will get softer and become more moist