Begin by draining the juice from the crushed pineapple into a measuring cup, ensuring you have a total of 3 cups of liquid. Heat this mixture in the microwave for about 3-4 minutes until it's steaming hot but not boiling.

In a large serving dish, combine the hot liquid with the raspberry Jello. Stir vigorously for approximately 2-3 minutes until the Jello is completely dissolved.

Transfer the Jello mixture to the refrigerator and allow it to cool until it starts to set, which should take about 45 minutes.

While the Jello is cooling, chop the crisp Granny Smith apple and optional pecans into bite-sized pieces. Once the Jello has thickened just enough, gently fold in the chopped apple, crushed pineapple, and nuts.

Return the salad to the refrigerator and let it set completely, which should take at least another hour but preferably overnight.