From Veganomicon.
Among the common condiments, mustard truly is the best. The intro to this recipe claims it’s for mustard lovers only, so I had to make it.
Mix 2 tbsp cornstarch (I used arrowroot) and 1/4 cup vegetable broth and set aside. Over medium heat, saute 3 garlic clovers and 1/2 tsp thyme for about a minute. Add 1/2 cooking wine (white or sherry) and 1 tbsp soy sauce and up the heat. When it’s boiling, lower heat and simmer for a few minutes. Add 1/4 cup dijon mustard, 1 tbsp lemon juice, 2 tbsp capers with brine, and cornstarch mixture. Stir often. When it’s bubbling, lower heat and simmer for a few more minutes. Should be pretty thick.
I used this with the seitan cutlets in a french dip-style dinner. I really like this sauce–the capers and wine give it a great kick. I made it again as a dipping sauce for artichokes. I didn’t have lemon juice, so I substituted some Gordon’s Vodka–couldn’t tell the difference. Sauce was good, but overpowered the artichoke.