Arrange a rack in the lowest position of the oven and heat the oven to 350°F. Lightly coat an 8-inch square baking dish or 6 (6- to 8-ounce) ramekins with cooking spray. Place the ramekins on a baking sheet. Bring 1 cup water to a boil in a kettle or small saucepan, then turn off the heat.

Whisk 1 cup plus 2 tablespoons all-purpose flour, ¾ cup granulated sugar, 1 ½ teaspoons baking powder, 1 teaspoon ground cinnamon, 1 teaspoon kosher salt, and ½ teaspoon baking soda together in a large bowl.

Stir in ¾ cup whole milk, 4 tablespoons melted and cooled unsalted butter, and 1 teaspoon vanilla extract with a flexible spatula until smooth.

Stir ⅔ cup packed dark brown sugar and the 1 cup boiled water together in a small bowl.

Option 1: Baking dish. Transfer the batter to the baking dish and spread into an even layer. Pour the brown sugar mixture over top. Do not stir. Sprinkle evenly with ⅔ cup chopped pecans.

Option 2: Ramekins. Divide the batter between the ramekins (about a heaping ¼ cup each). Divide the brown sugar mixture between the ramekins, pouring it over the batter. Do not stir. Sprinkle ⅔ cup chopped pecans on top (about 1 ½ tablespoons each).

Bake until the top of the pudding cake is set and a tester inserted into the cake portion comes out with just a few moist crumbs, 35 to 40 minutes. Place on a wire rack and let cool for at least 20 minutes before serving. Serve dusted with powdered sugar or topped with whipped cream if desired.