Asparagus with Hollandaise
1 bunch asparagus, trimmed
1 lemon, halved
2 tablespoons butter
1 tablespoon all-purpose flour
1 cup milk
1 egg yolk
In a large saucepan, combine the asparagus, the juice of half of the lemon, and about 1" water. Cover and bring to a boil over medium-high heat. Reduce the heat to medium and cook for 2 minutes or until the asparagus is bright green and crisp-tender. Rinse the asparagus under running cold water until cool, then drain.
In a small saucepan, melt the butter over medium heat. Reduce the heat to low, add the flour, and cook, stirring constantly, for 2 minutes or until the mixture is bubbly. Stir in the milk and cook, stirring frequently, for 5 minutes or until the milk thickens. Meanwhile, place the egg yolk in a medium bowl.
While whisking the yolk constantly, slowly pour 1/2 cup of the warm milk mixture into the egg yolk. Continue whisking until smooth and yellow.
While whisking the remaining milk mixture constantly, slowly return the egg yolk mixture to the saucepan. Continue to cook, stirring frequently, for about 5 minutes, making sure to not let it curdle. Remove from the heat and squeeze in the remaining lemon juice. Cool and serve as a dip for the asparagus.
Tips: Should your sauce curdle, simply pour it through a fine strainer to remove any cooked egg.