White Potato-Egg Sandwich Loaf

Ingredients

• 1 cup lukewarm water
• 2 1/2 teaspoons instant yeast
• 1 tablespoon demerara sugar
• 1/2 cup instant mashed potatoes
• 1/4 cup semolina flour
• 1 egg
• 1/4 cup Greek yogurt
• 1 teaspoon salt
• 2 cups bread flour

Directions

1. Combine the water, yeast, and sugar in the bowl of a stand mixer. If you have any doubts about the yeast, pause for a few minutes and look for foaming before moving on. Whisk in the potato flakes and semolina, then leave the mixture alone for 10 minutes so the potatoes can absorb liquid and the yeast can wake up.
2. Add the egg, yogurt, salt, and bread flour. Set the bowl on the mixer, fit it with the dough hook, and knead until the dough pulls away from the bowl, looks glossy, and feels elastic. It will still be quite soft and a little sticky, even when it is exactly where you want it.
3. Take the bowl off the mixer and coat the doughball lightly with olive oil on every side. If you need that mixer bowl, transfer the dough to a clean bowl first. Cover with plastic wrap and let the dough rise until doubled, about an hour.
4. Heat the oven to 350 degrees F, then dust the bottom of a 9-by-5-inch loaf pan with cornmeal. Turn the dough out of the bowl and shape it into a log that fits the pan. Cover the pan with plastic wrap and let the dough rise again until doubled. This rise should be roughly half as long as the first, about 30 minutes.
5. Cut a slash across the top of the loaf, then bake at 350 degrees F for 30 to 40 minutes, until the crust is well browned.