Step 1: Prepare your workspace by generously buttering a large baking sheet, marble slab, or heatproof silicone mat. Have buttered kitchen shears or a knife ready for cutting.
Step 2: In a heavy-bottomed saucepan, combine the granulated sugar, light corn syrup, water, 2 tablespoons of butter, and salt. Stir over medium heat until the sugar completely dissolves.
Step 3: Insert a candy thermometer, ensuring it doesn't touch the bottom of the pan. Increase the heat to medium-high and bring the mixture to a rolling boil. Do NOT stir after it begins boiling.
Step 4: Continue cooking, without stirring, until the candy thermometer reaches exactly 250°F (120°C). This is the hard-ball stage and is crucial for the taffy's texture.
Step 5: Immediately remove the saucepan from the heat. Carefully stir in the vanilla extract, food coloring (if using), and any optional flavor extract. The mixture will bubble vigorously.
Step 6: Pour the hot taffy mixture evenly onto your prepared buttered surface. Allow it to cool undisturbed for about 15-20 minutes, or until it is warm enough to handle comfortably with buttered hands or heatproof gloves, but not too hot to touch.
Step 7: Generously butter your hands or put on heatproof gloves. Begin pulling the taffy: grab the mass, stretch it out, fold it back onto itself, and twist repeatedly. As you pull, it will gradually become lighter in color, more opaque, and significantly firmer and more elastic. Continue pulling for 10-15 minutes until it achieves a satiny sheen and is very pliable.
Step 8: Once pulled to the desired consistency, roll the taffy into long, uniform ropes, about 1/2 inch in diameter. Using buttered kitchen shears or a knife, cut these ropes into bite-sized pieces, approximately 1 inch long.
Step 9: Immediately wrap each piece of taffy tightly in individual squares of wax paper, twisting the ends to seal in freshness and prevent sticking. Store in an airtight container at room temperature for up to two weeks.