1-First Step: Setup and mise en place Line an 8 by 8 inch glass baking dish with aluminum foil. Make sure the foil overhangs two opposite sides so you can lift the finished block out easily. Measure and divide the white chocolate morsels and the sweetened condensed milk into six equal portions ahead of time. For each layer you will use 1/2 cup white chocolate morsels and 3 tablespoons plus 1 teaspoon sweetened condensed milk.

2-Second Step: Make the first layer Combine 1/2 cup white chocolate morsels and 3 tablespoons plus 1 teaspoon sweetened condensed milk in a small microwave-safe bowl. Microwave for 30 seconds, then stir until smooth. If it is not completely melted, microwave an additional 10-15 seconds and stir. Avoid overheating to prevent seizing. Add your chosen food coloring drops for the first color (for vibrant reds, you will need 16 drops; for other standard colors use 8 drops; see ingredient notes for purple and orange). Spoon and spread the colored mixture evenly into the prepared 8×8 dish. Use an offset spatula or the back of a spoon to smooth the surface. Chill in the refrigerator for 10 minutes to let the first layer firm up just enough to support the next layer without blending.

3-Third Step: Repeat for each layer Repeat the melting process for the next color: combine 1/2 cup white chocolate morsels with 3 tablespoons plus 1 teaspoon sweetened condensed milk in a small bowl, microwave 30 seconds, stir until silky, add the food coloring for the color you want, then spread evenly over the chilled layer. Chill 10 minutes before adding the next one. Continue this process for six layers total. Because each layer uses the same base, you can easily change the flavor of a specific layer by adding 1-2 teaspoons of extract (vanilla, almond, orange) or 1-2 tablespoons of powdered freeze-dried fruit. For color-safe flavor additions, prefer dry extracts and powders rather than fruit purees.

4-Fourth Step: Final chill and remove After the sixth layer is poured and smoothed, refrigerate the entire pan for at least 2-3 hours until fully set. When firm, lift the block out by the foil overhang and peel away the foil. Place on a cutting board and cut into squares with a sharp knife. For cleaner cuts, let the fudge sit at room temperature 5-10 minutes or dip the knife in hot water, wipe it dry, and slice.

5-Final Step: Serving and storing Arrange squares on a platter or pack into an airtight container. The recipe suggests storing at room temperature for up to two weeks, but for best texture and food safety in warm environments, refrigerate or keep in a cool spot.