¾ to 1 cup water, at 110˚F/43˚C
2 teaspoons active dry yeast
4 teaspoons sugar
1 sweet potato, roasted tender and peeled
3¼ cups all-purpose flour
2 teaspoons kosher salt
Olive oil, for grilling
¼ cup Madeira wine
2 heads garlic, roasted and peeled
½ cup butter, room temperature
2 tablespoons minced pecans
1 tablespoon finely minced shallot
1 tablespoon orange zest
Kosher salt and freshly ground black pepper
Prepare the bread dough
In a small bowl, whisk ¼ cup of the warm water, the yeast and 1 teaspoon of the sugar until the yeast dissolves. Let rest 10 minutes.
In a food processor, pulse the sweet potato with the remaining 3 teaspoons of sugar, the flour and salt. With the processor running, add the yeast mixture and ½ cup more warm water. Mix until the dough forms a ball, adding more warm water if needed. Transfer the dough to a large oiled bowl, turning to completely coat with oil. Cover with plastic wrap and allow the dough to rise in a warm place until it doubles in size, about 1½ hours.
Transfer the dough to a floured work surface and knead until smooth and pliable. Divide the dough evenly into 4 balls. Flatten the balls into 5- to 6-inch rounds, cover with a dry kitchen towel and let rest for 45 minutes.
Make the Madeira butter
In a small saucepan over medium-high heat, simmer the wine until it reduces to 1 tablespoon, about 10 minutes. In a medium bowl, mash the roasted garlic into a paste. Stir in the butter, pecans, shallot, orange zest and reduced wine. Season to taste with salt and pepper.
Grill the bolo bread
Heat an outdoor grill or indoor cast iron grill to high. Brush one side of each dough round with olive oil and grill, oiled side down, until charred and golden brown. Press lightly with a spatula to keep the bread from puffing and ensure it caramelizes. Brush the top sides of the dough with olive oil and flip, grilling until golden brown. Serve with Madeira butter.