1. Preheat the oven to 200°C (390°F). Lightly grease a 23cm (9 inch) baking dish/pie dish and set aside.

2. Wash, dry, half, and stone the damson plums. Transfer to the baking dish and set aside.

3. Combine the ground almonds, sugar, flour, and cinnamon in a large bowl. Add the milk, eggs, and vanilla extract and mix until well combined. Pour the mixture over the plums, sprinkle with the sliced almonds, and bake for about 35-45 minutes – or until a wooden skewer inserted into the center comes out clean. Take the Clafoutis out of the oven and let cool down. Dust with a little confectioners’ sugar, if desired, and serve still a bit warm or completely cooled.