Preheat oven to 180C/160C Fan. Then grease muffin tins with 12 holes, and line with a thin strip of baking paper in each.
Using an electric hand-whisk, whip the butter and sugar together until pale and fluffy. Add two eggs and half the ground almonds, mixing until fully combined. Then add the remaining two eggs and ground almonds, mixing again until combined. Fold in the flour, baking powder and salt by hand until just combined. Then pour half the batter into a separate bowl.
Place 30ml of the milk into a small bowl, and heat in the microwave for 10 seconds until lukewarm. Mix in the ground coffee and cocoa powder, then pour this into one half of the batter. Mix thoroughly, then set aside. Pour the remaining milk and cardamom into the other batter.
Spoon approx. 1tbsp of the cardamom batter into each muffin tin hole, then spoon approx. 1tbsp of the coffee batter into each hole. Slightly swirl with a knife, and then bake for 30 minutes or until a skewer comes out clean. Leave to cool in the tins for a few minutes, before removing and leaving to cool completely.
Teacakes can be kept in an air-tight container for 3-4 days.