How to Make It
In a small skillet, toast the mustard seeds over moderate heat until they begin to pop, 1 minute. Immediately transfer them to a bowl and cover with a lid to stop the popping. Let the seeds cool completely.
Transfer the mustard seeds to a spice grinder. Add the sugar and salt to the mustard seeds and grind to a powder.
Return the powder to the skillet. Add the turmeric, vinegar, oil, Worcestershire sauce, Tabasco and 3 tablespoons of the water. Cook the paste over moderate heat, stirring constantly, until it's sizzling, about 5 minutes. Stir in the remaining 1/3 cup of water and transfer to a bowl. Refrigerate overnight before serving.