For the jam, mix jam sugar, frozen fruit, 1 packet of vanilla sugar and lemon juice in a large pot. Bring to the boil at medium heat, let it boil for about 4 minutes until it becomes bubbly. Immediately fill into sterile jars with twist-off lids, close them and put them on the lid for about 10 minutes.
Then turn around and let it cool down.
Meanwhile whisk buttermilk and egg. Mix flour, baking powder, baking soda, sugar and salt. Cut butter into cubes and add to the flour mixture. Mix quickly with your fingertips to a coarse crumbly dough.
Stir in the buttermilk and egg mixture briefly. Stir only until just enough to form a dough. Pour the dough onto a floured work surface and roll out to a thickness of approx. 1.5 cm. Cut out approx. 9 scones (6.5 cm Ø each) and place them on a baking tray lined with baking paper.
Bake in a preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for 10-12 minutes. Remove and let cool on a cake rack.
In the meantime, stir orange juice, clotted cream and 1 sachet of vanilla sugar in a tall container with the whisks of the hand mixer until smooth. Cut the cooled scones in half horizontally. Spread the undersides with approx. 1 tbsp. cream and jam each.
Put the topsides on top of it. Use the rest of the jam for other purposes.