In a heavy bottomed saucepan melt together the brown sugar, evaporated milk, butter and salt. Bring to a boil, stirring constantly then lower the heat to medium. Continue to cook until soft ball stage [238°F] stirring periodically to prevent sticking. This may take as long as 15 minutes, be patient and use a good candy thermometer, don't guess.

While the fudge is cooking liberally butter the bottom and sides of an 8 x 8 inch non-stick metal pan.

Remove the fudge from the heat and mix-in the toasted walnuts, miniature marshmallows and vanilla. Stir until the marshmallows have completely melted.

Add 1/2 cup English toffee bits. Mix well,

Pour into the buttered pan. Immediately sprinkle the remaining toffee bits on top gently pressing into the fudge.

Cool completely, then cut into squares.