In the bowl of a stand mixer, sprinkle yeast over lukewarm water. Allow it to proof for about 5 minutes, until foamy.

Add in sugar, softened vegan butter, and sweet potato purée and whisk or stir by hand to combine.

Add in 4 cups bread flour and salt. Fit the stand mixer with the paddle attachment and mix on medium speed until the dough comes together in one rough piece.

Switch to the dough hook attachment and knead on medium speed for 8-10 minutes. The dough will go from shaggy to smooth and elastic. It should be a little tacky but should easily clear the sides of the bowl. If the dough seems excessively sticky or wet, add in extra bread flour 1 tbsp at a time, kneading on medium speed between additions. (How much you'll need can vary depending on factors like humidity and the protein content of your specific brand of flour.)

Lift the dough out of the bowl and form it into a ball. Drizzle a little bit of oil in the bowl, then place the dough back into the bowl and turn it over to coat it with the oil.

Cover the bowl with a clean, damp kitchen cloth and allow to rise in a warm place until roughly doubled in size. This will take about 1 hour on average, but if your kitchen is particularly cold it can take up to 2 hours.

Turn dough out and form it into your desired shape. You can do a simple 3-strand braid, or scroll to the "Shaping the Challah" section in the blog post for more ideas. 

When forming the strands, divide the dough into the required number of pieces. (I like to use a scale for accuracy.) Then flatten each piece into a rough rectangle, and then roll it up like a cigar. Then roll each piece out using your palms, into a long strand, tapering the ends. This is similar to shaping a baguette.

Note: Avoid using too much flour on your work surface when rolling out the strands. You can use a small amount to keep the dough from sticking to the surface or your hands, but if you use too much, it will be hard to shape your strands cleanly. We want the dough to be able to stick to itself when you roll it into strands. Generally if the dough is the correct texture, you should be able to roll it out on a clean surface without it sticking.

Once the loaf has been shaped, transfer it to a baking tray lined with parchment or a silicone baking mat. You can brush it with a vegan egg wash substitute if you like (see notes). Then allow it to rise for 30 minutes to 1 hour. This will vary depending on the temperature in your kitchen. We don't need the loaf to double in size, but we want it to become puffy enough that if you poke it with a finger, the indentation remains. If it springs back quickly, it needs more time.

Start to preheat your oven to 375°F when the loaf is almost ready to bake.

If using, brush the dough with another layer of egg wash substitute. Try not to drip extra on the tray, as the sugars in it tend to burn.

Bake the loaf for 35-40 minutes. Check on it at the 20 minute mark. Especially if you used the egg wash substitute, you may find it is starting to get a bit dark. If this is the case, tent it loosely with a sheet of aluminum foil so it can continue to bake without browning excessively. The bread is ready when it's evenly golden brown and sounds hollow when tapped on the bottom.

Remove the dough from the oven. Transfer it to a cooling rack if you have one, and allow it to cool to room temperature. Bread continues to cook as it cools, so it's generally not recommended to cut into it while it's still steaming hot. This tends to give it a gummy texture.