Dissolve salt in water. Immerge the pork brains in the salt water and soak overnight in the refrigerator.
The next day, drain the salt water. Remove the membrane from the pork brains and discard it. Rinse the pork brains well with clear water.
In a separate bowl, beat the egg. Add flour and baking powder to make a batter. If the batter is too thick, add more milk, a little at a time.
Dredge the pork brains in the batter. Pan fry until well done, turning only once. They're done when the internal temperature of the pork brains reaches 145°F.