Sweet Potato Focaccia Bread

Apparently potatoes are really good in bread-making because they are starchy and give the bread a nice softness and airyness. I pretty much followed the recipe in the America's Test Kitchen family baking book just swapping sweet potato for regular potato. I was really happy with the result and the dough was not difficult to handle at all, despite the high hydration which is typical of focaccia doughs.

Sweet potato vs regular potato:
-Helps blood sugar remains more stable than regular potatoesa because they have more fiber.
-Good source of copper, vitamin B6, potassium and iron.
-High in Vitamin A, C and antioxidants
-Grown by vine or root cuttings (instead of seeds)
-The flower "Morning Glory" belongs to the same botanical family
-Completely different family from a yam
-Lastly, it makes cool looking orange-tinted bread

Sweet Potato Focaccia Bread
10" x 14" x 1" | adapted from Cook's Illustrated

Dough:
1 1/3 cup cooked sweet potato, mashed
1 1/2 teaspoons instant yeast
3 1/2 cups unbleached all-purpose flour
1 cup water (warm, 105 to 115 degrees)
2 tablespoons olive oil , plus more to grease bowl/pan
1 1/4 teaspoons salt

Topping:
2 tablespoons extra-virgin olive oil
2 tablespoons fresh rosemary
3/4 teaspoon sea salt , coarse

1. In large bowl of electric mixer or work-bowl of food processor fitted with steel blade, mix or pulse yeast, 1/2 cup flour, and 1/2 cup warm water until combined. Cover tightly with plastic wrap (or put work-bowl lid on) and set aside until bubbly, about 20 minutes. Add remaining dough ingredients, including sweet potato. If using mixer, fit with paddle attachment and mix on low speed (number 2 on KitchenAid) until dough comes together. Switch to dough hook attachment and increase speed to medium (number 4 on KitchenAid); continue kneading until dough is smooth and elastic, about 5 minutes. For food processor, process until dough is smooth and elastic, about 40 seconds.

2. Transfer dough to lightly oiled bowl, turn to coat with oil, and cover tightly with plastic wrap. Let rise in warm, draft-free area until dough is puffy and doubled in volume, about 1 hour.

3. With wet hands (to prevent sticking), press dough flat into generously oiled 15 1/2-by-10 1/2-inch jelly roll pan or halve and flatten each piece of dough into 8-inch round on large (at least 18" long), generously oiled baking sheet. Cover dough with lightly greased or oil-sprayed plastic wrap; let rise in warm, draft-free area until dough is puffy and doubled in volume, 45 minutes to 1 hour.

4. Meanwhile, adjust oven rack to lower-middle position and heat oven to 425 degrees F. With two wet fingers, dimple risen dough. For the topping: Drizzle dough with oil and sprinkle evenly with rosemary and coarse salt, landing some in pools of oil.

5. Bake until focaccia bottom is golden brown and crisp, 23-25 minutes. Transfer to wire rack to cool slightly. Cut rectangular focaccia into squares or round focaccia into wedges; serve warm. Can store on counter for several hours and reheated just before serving. Or, wrap cooled focaccia in plastic and then foil and freeze for up to 1 month; unwrap and defrost in 325-degree oven until soft, about 15 minutes.