This one has been in my recipe box for some time. No cocoa but sharing with you.
2-4 squares unsweetened chocolate
1/2 c butter
1/2 tsp salt
3 c sugar
1 large can evaporated milk
Melt chocolate, butter and salt in double boiler. Add sugar 1/2 cup at a time, alternating with the milk and stirring well after each addition. Continue stirring until well mixed. Serve hot over ice cream. Makes 3 cups. Store in refrigerator.