1. In a large bowl, combine the vegetables and salt and toss to mix well
2. Cover and let stand overnight.
3. Drain the mixture, squeezing out as much liquid as you can.
4. Turn into an earthen-ware crock or large glass jar.
5. In a stainless steel or enamel coated saucepan, combine the mustard seeds, brown sugar, and vinegar and boil.
6. Pour the hot liquid over the vegetables and stir to mix.
7. Once cooled completely, cover and refrigerate.