Updated: Nov 25, 2020
One of the easiest ways to use up sourdough starter discard is to make a galette. Plus, assembling a galette is super simple. Try this sweet potato galette recipe for a perfect fall treat with a buttery, flaky crust. Note: The galette pictured is only mildly sweet, which is how I prefer it. I've included instructions for a maple tahini drizzle if you want to amp up the sweetness (like my husband does).
New to sourdough baking? Start here.
Sourdough Discard Sweet Potato Galette
Makes one medium-sized galette
This recipe requires a mixing bowl, measuring cups, plastic wrap, parchment paper or a nonstick baking mat, and a sheet pan for baking
For the crust
1 cup flour
1 teaspoon granulated sugar
1 stick (8 tablespoons) cold unsalted butter cut into chunks
1/4 cup unfed starter discard
For the sweet potato topping
1 large sweet potato
2 tablespoons unsalted butter
1/4 teaspoon cinnamon
1/4 teaspoon nutmeg
1/4 teaspoon vanilla extract
Granulated sugar, less than 1/4 cup
Optional tahini maple drizzle
2 tablespoons tahini
2 tablespoons maple syrup
Make the dough
1. In a medium-sized bowl, mix 1 cup flour and 1 tsp sugar.
2. Using a pastry cutter (or your hands), cut in the 8tbsp of cold, unsalted butter into the flour mixture until pebble-sized pieces remain.
3. Add 1/4 cup unfed starter discard to the flour and butter mixture. Mix and knead gently until the dough comes together and forms a ball. You may need to add 1 - 2 tablespoons of water to make sure the dough comes together, depending on your sourdough starter.
4. Wrap the ball of dough tightly with plastic wrap and place in the fridge for at least 2 hours. I often make this dough the day before and leave it in the fridge overnight to work with the following day. *Note: If you want to make this dough ahead and freeze it to use later, you can. Just be sure to take the dough out of the freezer and place it in the fridge a full day before you plan to bake with it so it can fully defrost.
Assemble the galette
5. When you're ready to assemble and bake the galette, preheat the oven to 400 F and remove the dough from the fridge.
6. Wash, peel, and slice your sweet potato into thin rounds about 1/8 inch thick.
7. Lightly flour a counter top and roll out the dough until it's about 1/4 inch thick using a rolling pin (or a wine bottle wrapped in plastic in a pinch). The beauty of a galette is that the shape isn't important and an imperfect shape works just fine. As long as the dough is rolled out so that it forms a large, flat surface on which to put the sweet potato slices, you're good.
8. Place the rolled out dough onto a baking sheet covered with parchment paper, or a non-stick baking mat.
9. Arrange the sweet potato slices on the center of the dough so that they're spread evenly with about two inches of space around the edges. Again, making them pretty is not necessary here.
10. Fold the edges of the dough in and over the top of the sweet potatoes. This will form the ring of flaky, butter crust around the outside of the galette.
11. Melt 2 tbsp of unsalted butter in the microwave.
12. To the butter, add 1/4 tsp each of cinnamon, nutmeg, and vanilla extract. Mix well.
13. Pour or brush the spiced butter mixture over the top of the entire galette, crust and sweet potatoes alike.
14. Sprinkle the galette with granulated sugar, covering the crust and filling generously.
15. Place the baking sheet in the middle rack of the oven and bake for 30-40 minutes until the crust is golden brown and the sweet potato slices soft. Allow to cool for 10 minutes before serving.
If serving with tahini maple drizzle
15. Mix 2 tbsp each of tahini and maple syrup well, drizzle over the top of the galette after it is out of the oven and has cooled. Note: You may need to add a teaspoon or so of water if your tahini is very thick. If so add water little by little to the mixture until you get a creamy, pourable blend.
Slice and serve. Goes very well with vanilla ice cream.