Bloom the yeast: Whisk the water, maple syrup and yeast together in a large bowl. Cover the bowl and let the yeast bloom until foamy, about 15 minutes.
282 grams water, 56 grams maple syrup, 7 grams active-dry yeast
Make the dough: Stir the sourdough discard, whole wheat flour and salt into the yeast mixture until no dry bits of flour remain. Switch to your hands and knead until a cohesive dough forms.
113 grams sourdough discard, 450 grams whole wheat flour, 9 grams salt
Knead the dough into the oil until completely absorbed. The dough should start greasy and gradually become smoother and less sticky. Cover the bowl with plastic wrap and let the dough rest for 15 minutes. * If using a stand mixer, mix the dough ingredients except for the oil. Once a cohesive dough forms, knead the dough with a dough hook and slowly stream the oil into the bowl until completely incorporated about 5 minutes. 56 grams olive oil
Strengthen the dough: Turn the dough out onto a lightly floured work surface. Knead the dough by folding it in half, then pressing and pushing with the heel of your hand. Continue this process until the dough becomes smooth and elastic, about 5 to 10 minutes.
First rise: Round the dough into a tight ball, and transfer it to a clean, lightly oiled bowl. Spread oil on top of the dough to prevent it from drying out.
Cover the bowl with plastic wrap and set it in a warm place until doubled in volume, about 45 minutes to 1 hour.
Prep: Preheat the oven to 400 F. Line a 9 by 4-inch Pullman pan (see note) with parchment paper or brush liberally with oil.
Toss the toasted sunflower seeds and sesame seeds on a plate. Set aside.
40 grams sunflower seeds, 10 grams sesame seeds
Shape the dough: Turn the dough out on a lightly floured work surface. Divide the dough into 5 even portions.
Working with 1 portion of dough at a time. Flatten the dough into a rough rectangle, and fold the corners towards the center. Turn the dough over, cup the dough and drag it on your work surface in a rounding motion to create a smooth, taut surface.
Brush the top of the dough with water and coat the top of each ball in the seed mixture. Nestle the dough in the prepared pan. Repeat with the remaining portions of dough, arranging them in a zigzag pattern.
Final Proof: Cover the loaf pan with plastic wrap. Let the dough rise untouched in a warm place. The dough should fill your pan and rise about ½ an inch above the rim, about 30 to 45 minutes.
Bake: Bake the dough for 10 minutes at 400 F. Without taking the loaf out of the oven, turn the temperature down to 350 F and continue baking for another 30 to 45 minutes or until the loaf registers at 200 F when probed with an instant-read thermometer.
Move the bread to a wire rack and let it cool completely, about 2 hours (ideally overnight) before slicing.