Mix both types of flour and salt in a mixing bowl. Chop the hazelnuts, cashews, and almonds, and mix with sunflower seeds, flaxseeds, and 60g of rolled oats.

Heat the oat drink, crumble in the yeast, and stir until dissolved. Add the maple syrup. Pour the yeast mixture into the flour mixture and knead with a dough hook or by hand for about 5 minutes.

Add the nut and seed mixture, and knead for another 5 minutes until a smooth dough forms. If necessary, add more spelt flour. Cover the dough and let it rise in a warm place for about 1 hour.

Line a baking sheet with parchment paper. Knead the dough on a lightly floured surface and divide into 10 equal pieces. Shape each piece into a roll, place on the sheet, and make a cross cut on top. Let rise for another 30 minutes.

Preheat the oven to 200°C (392°F). Brush the rolls with water and sprinkle with the remaining 15g of rolled oats. Bake for 20 minutes with a dish of hot water in the oven to create steam.