Spread nuts evenly in bottom of a greased 8 x 11-inch baking dish.
Grease sides of a large stockpot.
Combine next 6 ingredients in stockpot and cook over medium-low heat, stirring
constantly until sugar dissolves. Using a pastry brush dipped in hot water, wash
down any sugar crystals on sides of pan. Attach candy thermometer to pan making
sure thermometer does not touch bottom of pan. Increase heat to medium and bring
to a boil. Do not stir while syrup is boiling. Cook until syrup reaches soft ball
stage (approximately 234 to 240 degrees F).
Test about 1/2 teaspoon syrup in ice water. Syrup should easily form a ball in
ice water but flatten when held in your hand.
Place stockpot in 2 inches of cold water in sink.
Add liqueur to syrup; do not stir until syrup cools to approximately 110 degrees
Add chocolate and beat fudge using medium speed of an electric mixer until it
is no longer glossy and thickens. Pour over nuts.