In a bowl, mix the flour, oats, walnuts (chopped coarsely with a nut chopper).
Add the sugar and baking powder and stir the dry ingredients well. Remove the pits from the fresh dates.
Roll the dates in the flour so they don't stick to the hands, cut them as finely as possible using scissors. Add the vanilla, oil and carbonated water, stir and combine the products.
The result is a sticky dough. Sprinkle 2-3 tbsp white flour on the table and pour in the mixture, then finish kneading until the dough takes in the flour and becomes smooth in your hands.
Cut it into 2, stretch out each part into a wick about 2″ (5 cm) in diameter. Make cuts along each wick, every 1/2″ (1 cm). Press each of the resulting parts carefully between your palms to form small biscuits.
Arrange them into a large tray onto baking paper.
Preheat the oven to 356°F (180 °C), put the biscuits to bake for 12 min. I baked with the fan on. While still warm, sprinkle them with a little powdered sugar.