The day before, mix 500 g flour and about 1 1/2 teaspoon salt in a bowl. Crumble the yeast and stir with 300 ml ice-cold water until smooth. Add to the flour and knead to a smooth yeast dough with the dough hooks of the mixer. Cover and leave to rise overnight in the refrigerator.
The next day, line two baking trays with baking paper. Preheat oven (electric cooker: 225 °C/circulating air: 200 °C/gas: see manufacturer). Divide the dough into 12 equally sized pieces. Use floured hands to form round or oblong rolls from the dough pieces and place them on the baking trays. Score them crosswise or lengthwise with a floured knife.
Fill a small ovenproof dish with water and place it on the bottom of the oven. Bake rolls in the hot oven for 12-15 minutes one after the other. Take them out and let them cool down on a grid. Serve rolls lukewarm or cooled down.