2 (6-ounce) mahi mahi filets2 tablespoons peppercorns, lightly crushed2 tablespoons vegetable oil2 tablespoons butter, divided1 shallot, minced3 tablespoons brandy or Cognac1/2 cup chicken stock1/2 cup heavy cream1 teaspoon Dijon mustardSalt to tasteSeason fish lightly with salt, then press peppercorns onto the top of each fillet. Once it is melted, add shallot and sauté until translucent, about 2 minutes. Add brandy and let reduce by half, about 1 minute. Whisk in chicken broth and cream and let reduce until a thick sauce forms, about 7 minutes. To serve, spoon sauce onto plate and place fish on top.