Grease and line a bread loaf pan with parchment paper. Set aside.

In a large bowl, mix together the rye starter, flour, seeds, salt and water using your hands (or a large mixing spoon if you don't want to get sticky) until completely combined. Spoon the dough into the greased and lined loaf pan.

Wet your hands with water and gently but firmly press the dough evenly out to the corners of the loaf pan. Smooth the top of the dough, wetting your hands again if necessary. Sprinkle extra sunflower seeds on top (optional).

Cover the loaf pan to prevent the dough from drying out. Plastic wrap, a plate, or a tea towel are good options. Place in the fridge overnight to rest.

Remove the loaf from the fridge, keep it covered and allow to proof in a warm spot (in the sunshine, near a heat vent/radiator, etc) until nearly doubled in size with visible cracks on top. This will usually take a 2 -3 hours depending on how warm the spot you chose is. Preheat the oven to 400 degrees F before the bread has finished proofing.

Bake for 50 minutes or until sides and bottom of loaf are a deep brown and the internal temperature of the bread has reached 200 degrees F.

Remove from the oven and run a small knife down any sides of the loaf pan that were not covered in parchment. Place the loaf on a cooling rack, remove the parchment paper and allow to cool completely before slicing.