- 1/2 (1 pound) package bacon, diced
- 3 tablespoons butter
- 1/3 cup all-purpose flour
- 1 quart chicken stock
- 2 egg yolks
- 1 cup heavy cream
- 1/2 cup coarse grain mustard (such as Dutch Zaanse mustard), or to taste
- 1 Granny Smith apple – peeled, cored, and diced
- Cook the bacon in a large, deep skillet over medium heat, stirring occasionally, until crisp and evenly browned, about 10 minutes. Pour off the fat and drain the bacon on a paper towel-lined plate.
- Melt the butter in a saucepan over medium-low heat. Add the flour and stir until the mixture becomes paste-like and light golden brown, about 5 minutes. Gradually whisk the chicken stock into the flour mixture and bring to a simmer over medium heat. Cook and stir until the mixture is thick and smooth, 10 to 15 minutes. Reduce heat to low.
- Beat the egg yolks and heavy cream together until blended. Slowly whisk 1/4 of the hot soup into the cream mixture and return the cream mixture to the soup pot. Whisk in the mustard; stir in the apple and bacon. Cook and stir until the soup is hot but not simmering.