Grease and line a deep 9-inch cake tin. Pre-heat the oven to 170oC (fan).
Roughly chop the cold butter into small cubes and put in a bowl with the rest of the crumble ingredients. Use your fingers to rub everything together to combine, some larger clumps are fine. Put the crumble mixture in the fridge while you make the cake.
Use an electric whisk to beat the butter and sugar together until light and creamy. Add the eggs, milk, lemon zest, cardamom and salt then beat again to combine.
Sift the flour and the baking powder into the batter then add the ground almonds and fold everything in gently until just incorporated.
Pour the mixture into the prepared tin and level it out with a spatula or the back of a spoon. If using fresh apricots, halve them lengthways and discard the stones. Arrange the apricots cut side up around the top of the cake then scatter the crumble over the top.
Put in the oven for 30-35 minutes until golden and a cake tester comes out clean. Leave to cool for five minutes before removing from the tin to cool completely
Lovely with a dollop of yoghurt, a scoop of ice cream or just a cup of tea. Best eaten the day of baking but you can store leftovers in an airtight container for up to three days.