Recipe adopted from Burp! Where Food Happens. [Recipe makes roughly 3/4 cup].
3 tablespoons unsalted butter
1/4 cup minced shallot
1/4 cup white wine (or light stock)
1/4 cup heavy cream
3 tablespoons Dijon mustard
1 tablespoon freshly squeezed lemon juice
Over a medium low heat, melt the butter in a small skillet and add the shallots. Cook the shallots for several minutes, or until tender. Add the white wine and whisk until most of the alcohol has evaporated. Whisk in the mustard and cream, heat through for a minute, and turn off the heat. Finish by whisking in the lemon juice, and season to taste.