1/2cup(100 grams) plus 3 tablespoons (36 grams) granulated sugar, divided
1/2cup(120 grams) sour cream
1/3cup(73 grams) firmly packed light brown sugar
1large egg (50 grams), room temperature
1teaspoon(4 grams) vanilla extract
2⅔cups(333 grams) all-purpose flour
1tablespoon(6 grams) apple pie spice
2teaspoons(10 grams) baking powder
2teaspoons(4 grams) ground cinnamon, divided
1½teaspoons(4.5 grams) kosher salt
¼teaspoon(1.25 grams) baking soda
1teaspoon(5 grams) unsalted butter, room temperature
1tablespoon(14 grams) unsalted butter, melted
Instructions
In a medium saucepan, bring cider to a boil over medium-high heat; cook, stirring occasionally, until reduced to ¾ cup (181 grams), 15 to 20 minutes. Remove from heat, and let cool completely.
Preheat oven to 350°F (180°C). Spray an 8½x4½-inch loaf pan with baking spray with flour. Line pan with parchment paper, letting excess extend over sides of pan.
In a large bowl, whisk together oil, 1/2 cup (100 grams) granulated sugar, sour cream, brown sugar, egg, and vanilla.
In a medium bowl, whisk together flour, pie spice, baking powder, 1 teaspoon (2 grams) cinnamon, salt, and baking soda. Gradually add flour mixture to sugar mixture alternately with reduced cider, beginning and ending with flour mixture, whisking until just combined after each addition. Spread batter into prepared pan.
Spoon room temperature butter into a pastry bag, and cut a ¼-inch opening in tip. Pipe lengthwise down center of batter.
Bake until a wooden pick inserted in center comes out with a few moist crumbs, 1 hour to 1 hour and 5 minutes. Let cool in pan for 10 minutes. Using excess parchment as handles, remove from pan, and let cool completely on a wire rack.
Using a pastry brush, brush melted butter onto cooled loaf. In a small bowl, whisk together remaining 3 tablespoons (36 grams) granulated sugar and remaining 1 teaspoon (2 grams) cinnamon; sprinkle onto loaf. Let stand until butter has been absorbed into loaf. Store in an airtight container for up to 3 days.
Notes
The line of butter on top of the batter helps create the signature domed rise and lengthwise crack in the top of a quick bread loaf—not mention a little extra flavor!