Toast the walnuts in a small pan over medium heat for 3–5 minutes, stirring frequently until fragrant and slightly browned. Let them cool.
Whisk together mayonnaise, honey, lemon juice, salt, and pepper in a small bowl to prepare the dressing. Adjust sweetness or acidity to taste.
Chop lettuce into bite-sized pieces, shred carrots, thinly slice red onion, and cut pineapple into chunks.
In a large salad bowl, combine lettuce, pineapple, carrots, red onion, dried cranberries, and cooled walnuts. Add feta if using.
Pour the dressing over the salad and toss gently until evenly coated. Serve immediately to maintain freshness and crunch.