For a more flavorful velouté, start with up to twice as much stock as is called for below and reduce it to the specified volume before whisking into the roux. If serving this sauce with fish or shellfish you may substitute 3 tablespoons Shrimp or Lobster Butter for the butter in the roux.
Heat in a small saucepan over medium heat, stirring occasionally, until hot:
Meanwhile, melt in a medium saucepan over medium-low heat:
Stir in:
Reduce the heat to low and cook, stirring constantly, until the roux smells nutty and is ivory colored, about 6 minutes. Remove from the heat and let cool for 2 minutes. Gradually whisk the warm stock into the roux. Return the saucepan to the heat and bring the sauce slowly to a simmer, whisking to prevent lumps. Cook over medium-low heat, stirring often and skimming any skin that forms on the surface, until thick enough to coat the back of a spoon, about 20 minutes; do not boil.
If desired, strain through a fine-mesh sieve and, just before serving, whisk in:
If you are using this sauce as is, season to taste with: