For the rhubarb-banana jam, clean, wash and cut the rhubarb into small pieces. Peel and chop the bananas. Weigh approx. 825 g rhubarb and 175 g bananas (1 kg fruit in total).
Mix in a large pot with jam sugar and lemon juice. Bring to the boil over a high heat while stirring and boil for at least 4 minutes while stirring continuously.
Pour the jam immediately into clean twist-off jars. Close the jars and place them on the lid for about 5 minutes. Turn them over again and let them cool down. Shelf life approx. 6 months.
For the scones, mix 250 g flour, sugar, 1⁄2 TL salt and baking powder in a bowl. Add butter in pieces and milk. Knead to a smooth dough with the dough hooks of the mixer. Cover and put in a cool place for about 15 minutes.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Line a baking tray with baking paper. Drain 125 g cherries well, dab dry if necessary (use the rest of the cherries and juice for other purposes).
Mix the cherries and 2 tablespoons of flour. With floured hands quickly knead into the dough (dough is a little sticky). Roll out the dough on a well floured work surface to a thickness of almost 2 cm. Cut out circles with a round cookie cutter (approx. 6 cm Ø).
Place dough circles on the baking tray. Knead the rest of the dough again and process as well. Cut out about 10 scones in total.
Whisk the egg and brush the dough circles with it. Bake in a hot oven for about 15 minutes. Remove the scones and let them cool down on a cake rack. Tastes best lukewarm. Serve with clotted cream and jam.