Melt butter in a granite pan. Add sugar, milk and molasses, stirring gently until sugar is dissolved. Boil slowly without stirring for five minutes. Add chocolate square and stir until melted. Boil again until a little of mixture dropped in cold water seems brittle. Take from range, add vanilla, beat until it begins to thicken, then pour into a buttered pan. Cool and mark into squares.
Cook in a small heavy saucepan; pour mixture into a buttered 9x5 or 8x4-inch pan.
A Little Book for a Little Cook (1905).