Start by melting the unsalted butter in a medium skillet over medium heat. Once melted, add the finely diced shallots along with a pinch of kosher salt. Sauté them until they soften, which should take about a minute.

After the shallots have softened, stir in the minced garlic and crushed black peppercorns. Cook this mixture for about 30 seconds until fragrant.

Next, you’ll whisk in the Dijon mustard, Worcestershire sauce, and all-purpose flour. Allow this to cook for about one minute; this step is crucial as it eliminates any raw flour taste.

Gradually add the low-sodium beef stock while continuing to whisk. Bring the mixture to a boil, then reduce the heat to let it simmer gently for about 10 minutes.

After simmering, stir in the heavy cream and let it continue simmering for another five minutes until thickened. Don’t forget to taste and season with salt as needed.