Deborah L. Arieda of Stanwood, Washington, developed this prize-winning recipe. Deborah says, "This bread is great served warm or cold. Within two hours from the start, you can spoon your favorite spread onto this rich, sourdough-flavored bread."
Combine the 1-1/2 cups of flour, the yeast, and the salt in a 3-quart bowl. Mix lightly and set aside.
Combine the yogurt, club soda, honey, and margarine in a 2-quart saucepan. Place over medium heat, and cook until the mixture is warm, but not too hot to touch with your fingers. Do not boil.
Add the yogurt mixture to the flour mixture, and stir to combine. Add the egg, and mix the ingredients with an electric mixer set at low speed until the dry ingredients are moistened. Increase the mixer to medium speed, and beat for 3 additional minutes. Add the remaining 1-1/3 cups of flour, and mix thoroughly.
Coat a 1-1/2-quart casserole dish with nonstick cooking spray, and pour the batter into the dish. Cover with a clean kitchen towel, and let rise in a warm place for 1 to 1-1/2 hours, or until the dough has reached the top of the dish.
Preheat the oven to 375°F (190°C). Bake the loaf for 35 to 40 minutes, or until golden in color. Allow the bread to cool in the dish for 5 minutes. Remove the loaf from the dish, and transfer to a wire rack. Serve warm or at room temperature.