Recipe for soft and light pumpkin toast

Peel and dice the pumpkin, steam until cooked, then mash into a puree and set aside. Mix all ingredients except butter and knead into a smooth dough. Knead the dough until it reaches the rough membrane stage, then add the butter and continue kneading until it reaches the fully developed stage, where it can be stretched into a strong, transparent film. Round the dough and place it in a proofing box for the first fermentation until it doubles or triples in size. To test if it's doubled or tripled in size, poke a hole in the dough with a floured finger; if the hole doesn't spring back, remove the dough and press it down with both hands to release the air, keeping the smooth side down. Divide the dough into twelve equal portions (178g each), round them, cover with plastic wrap, and let them rest for 15-20 minutes. Roll each rested dough portion into an oval shape, fold it into thirds, roll it out again, and then roll it into a cylinder. For the second fermentation, set the temperature to approximately 33 degrees Celsius and the humidity to 85%, and the time to approximately 60 minutes, observing the fermentation progress. Continue fermenting until the dough fills 8-9/10 of the loaf pan. Bake in a convection oven at 170 degrees Celsius for 25 minutes. Two loaves were the right color, while the other two were darker. I'm considering using 165 degrees Celsius next time.