Mix milk, sugar, butter, salt, and vanilla in a large heavy pan and bring to boil.
Add brown sugar and stir until it dissolves. Continue cooking and stirring mixture over medium heat until it reaches soft ball stage. Stir until thick enough (as for fudge). Drop by teaspoonful on a buttered pan or waxed paper or pour into buttered pan and cut into squares.
5 1/2 c
5 1/2 Tbsp
brown sugar, firmly packed