Mix the wet ingredients: In a medium mixing bowl, combine the water, sourdough starter, and honey. Stir until fully dissolved.
Prepare the seeds: Measure out your pumpkin seeds, sunflower seeds, millet, oats, and flax in a separate bowl. You can use them whole for convenience or crush them in a food processor—I prefer crushing them for better hydration and even distribution in the dough.
Combine dry ingredients: Add the rye flour, whole wheat flour, prepared seeds, and salt to the wet mixture. Stir until a thick, batter-like dough forms. No need to knead—just mix until well incorporated.
First rise (bulk fermentation): Cover the bowl and let the dough rest overnight or for about 12 hours at room temperature. It should expand and become slightly puffy.
Prepare the pan: After the first rise, line a bread pan with parchment paper or grease it well with butter and flour.
Shape and proof: Transfer the soft, batter-like dough into the prepared loaf pan. Smooth the surface and lightly dust with rye flour. Cover and let it rest for another 1-2 hours until it has risen slightly.
Preheat the oven: When the dough is nearly ready, preheat the oven to 450°F (230°C).
Bake: Once preheated, place the loaf in the oven and immediately reduce the temperature to 350°F (175°C). Bake for 60-75 minutes until deep brown and firm.
Cool completely: Remove the bread from the oven and carefully take it out of the pan. Place it on a cooling rack and let it rest for 12-24 hours to fully cool and set before slicing.
Enjoy!: Slice and serve with a generous amount of butter or your favourite toppings.