For the yeast dough, warm the milk lukewarm. Crumble the yeast into it, dissolve while stirring. Put 400 g flour, sugar, 1 pinch of salt and egg in a bowl. Add the yeast milk. Stir in with the dough hooks of the mixer, kneading 75 g butter in pieces until the dough is smooth and soft.
When the dough separates from the bowl, continue kneading for about 3 minutes. Cover and leave to rise in a warm place for about 1 hour.
Wash, halve and stone the plums. Grease a fat pan (deep baking tray; approx. 32 x 39 cm). Knead dough on some flour briefly. Spread on the baking tray with moistened fingers. Cover and let rise for about 20 minutes.
For the almond icing, meanwhile simmer 100 g butter, vanilla sugar, cream and brown sugar at low heat for about 3 minutes. Stir in almonds, simmer for 2-3 minutes. Leave to cool for about 15 minutes, stirring more often.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer).
Spread the plums on the dough and pour the almond icing over them. Bake in a hot oven for about 20 minutes. Let it cool down.