
I have previously shared a recipe made with regular sweet potato. It was such a delicious sandwich loaf.
Here is another delicious loaf made with addition of purple sweet potato. I have also added an egg to the dough, for extra softness.
Here are the details.
Ingredients
Sourdough Starter
- 7g sourdough starter
- 35g water
- 35g bread flour
Dough
- 300g bread flour (100%)
- 120g roasted and mashed purple sweet potato
- 125g water
- 1 large egg
- 30g sugar (10%)
- 60g of levain (20%)
- 6g salt (2%)
- 30g soft or melted butter(10%)
- 0.5 g dry yeast (optional, to reduce the sourness, can be added with water)
Directions
Day 1
Starter
- 10 pm add starter to the water and whisk together, add flour, mix well, cover loosely, let it sit at a room temp 74-78F for about 8-10 hours until starter reaches its peak (at least triples in volume).
- Roast purple sweet potato and let it cool. Mash it.

Day 2
Dough
- 8 am mix water, flour, purple sweet potato, egg, sugar, sourdough starter (60g on its peak, the rest use for future feedings), let it autolyse for 1 hour. During the autolyse process the flour becomes fully hydrated. This activates gluten development.
- 9 am mix dough on low speed of your mixing machine for 2-3 minutes, or KitchenAid on speed 3 for 3-4 minutes until well incorporated.

- Add salt, mix for a couple more minutes. The dough should come up together.
- Add soft butter, increase the speed to medium and mix for 10 more minutes until the dough is well incorporated and comes up together.
- Perform a windowpane test. Wet your hands and stretch the dough. You should be able to stretch it very thin, that’s a sign of a well developed gluten, and that your final product will have a soft and light structure.
- Cover and let the dough proof for 3-4 hours at 76-80F/ 24-28C.

- During that time perform 2 stretches and folds.
- The dough should become slightly puffy.

- 1 pm transfer the dough to the fridge for cold fermentation till the evening (for 8-9 hours).
- 10 pm remove the dough from the fridge.
- Shape as desired. I rolled it into a roll half length of a baking/loaf pan.
- Put a sheet of parchment paper on the bottom of your loaf pan, or spread butter and sprinkle some flour, inside your loaf pan.
- Transfer the shaped loaf into the loaf pan.
- Cover the dough and let it proof overnight 72F /22C until it doubles or more in volume. About 7-9 hours. Usually it doubles or more in volume by morning (6-7 am).
Day 3
- 7 am preheat the oven to 375F.
- Bake bread for 35-40 minutes until golden brown.

Enjoy your purple sweet potato sandwich loaf 🙏
What a lovely loaf and another great recipe, Natalya. Thank you!
Thank you, Patricia 🙏
Where do you get starter?
I have a recipe on my website 🙏
The last fermentation just at room temperature ?
The last fermentation just at room temperature ?
Hi! I’m planning on doubling this recipe so I can make a loaf for my friend. Will I need to increase proof time too or should I be able to tell by touch?
Hi!
Usually it should take the same amount of time.
Will steaming the potato make a difference vs roasting?
No, not at all 🙏
The last fermentation just at room temperature?
Last fermentation before shaping, yes, still room temp