Place the raspberry gelatin in a large mixing bowl. Pour in the boiling water and whisk for about 1 to 2 minutes, or until every gelatin granule has dissolved.

Stir the whole-berry cranberry sauce into the dissolved gelatin. Continue mixing until the sauce is mostly blended and the mixture looks evenly ruby red.

Add the very well-drained crushed pineapple, finely grated orange zest, and orange juice. Stir thoroughly so the fruit and citrus are distributed throughout the gelatin mixture.

Fold in the chopped walnuts or pecans if using. Use a gentle motion so the nuts remain evenly dispersed instead of collecting in one area.

Pour the mixture into a lightly greased 9-by-13-inch dish, a 2-quart serving dish, or a gelatin mold. Cover the dish and refrigerate for at least 4 hours, or until the salad is firmly set.

Serve the salad cold, either spooned directly from the dish or unmolded onto a platter. For the best texture and easiest unmolding, prepare it the day before serving.