Step by step method

1. Preheat the oven to 180°C and grease a square baking tin (30 x 30 cm).
2. First make the leavening agent - mix the yeast with half a cup of warm milk, two tablespoons of sugar and another two of flour. Set aside in a warm place to rise (7 - 10 minutes).
3. Sift the flour into a bowl add the margarine, add the leavening agent, eggs, egg yolks and ginger and mix well. Add the remaining warm milk with the brown sugar and vanilla. Knead the dough until elastic and no longer sticky. Place in a bowl, cover with clingfilm and leave in a warm place to prove until it has doubled in size (this will take approximately 40 minutes).
4. Once the dough doubles its volume, put it into the baking tin and sprinkle the plums on top.
5. Put all the ingredients for the crumble into a bowl and rub with your fingers until they are well combined. Sprinkle over the plums.Â
6. Bake for about 45 minutes. Check with a skewer or toothpick to see if the cake is ready. If you prick the cake with the toothpick and it is dry, not sticky, then the cake is ready to serve. If not, bake for a little bit longer then check again.Â
7. Let the cake cool and serve.