In a saucepan over low heat, combine margarine and chocolate. Melt, stirring frequently so the chocolate does not burn or stick. In a bowl, combine sugar, flour and salt. Stir in chocolate mixture. Beat eggs, then add them to batter with the vanilla. Stir until eggs are well blended, but do not beat the mixture. Line muffin tins with paper liners. Fill each one about two thirds full. Bake at 300ºF.  for 30 - 40  minutes.

Check to see if muffins are done by inserting a toothpick in one near the center of the muffin. If the toothpick does not come out clean bake for another 5 minutes. Let muffins cool 5 minutes before removing them from the pan. These taste very much like brownies. Keep any leftovers in a covered container, then rewarm them.