1-First Step: Prepare your workspace. Line a 9×13-inch pan with aluminum foil, extending over edges for handles. Lightly butter the foil to prevent sticking. Chop 1 cup walnuts if using, and measure all ingredients precisely. This mise en place keeps things smooth, especially for beginners. Set aside a heavy saucepan and wooden spoon.

2-Second Step: Combine the base mixture. In the saucepan, mix 3 cups sugar, ¾ cup butter, and ⅔ cup evaporated milk. Place over medium heat. Stir constantly with a wooden spoon to dissolve sugar fully, about 2 minutes. Bring to a full rolling boil. This prevents grainy kraft fudge texture.

3-Third Step: Boil to perfection. Once boiling, stop stirring. Let bubble until it reaches 234°F (soft-ball stage), about 4-5 minutes. Test by dropping a bit into ice water; it should form a soft ball. Wipe sugar crystals from pan sides with a wet pastry brush. Accurate temperature guarantees the authentic fantasy fudge set.

4-Fourth Step: Add flavor powerhouses. Remove from heat. Stir in 12 oz semi-sweet chocolate chips until melted. Add 7 oz marshmallow creme, 1 tsp vanilla, and nuts. Beat vigorously by hand for 3-5 minutes or with a mixer on low for 1-2 minutes. The mixture thickens and loses gloss, signaling readiness. This fantasy fudge marshmallow creme step creates creaminess.

5-Fifth Step: Pour and cool. Spread into prepared pan with a spatula. Cool at room temperature for 2 hours until firm. Avoid refrigerating early to prevent sweating. Lift out using foil, then cut into 1-inch squares for about 4 dozen pieces.

6-Final Step: Serve and enjoy. Store as directed below. Plate on a tray with parchment for parties. This method yields professional results for party hosts and baking enthusiasts alike. Total time: 25 minutes active, 2 hours cooling.