Cut each fennel bulb in half then place them flat side down. Using a sharp chef's knife, gently slice the fennel into thin strips. The thinner the pieces the better- you can also use a mandoline for this step.
Slice the apple in half and remove the seeds and core. Slice into thin wedges. If you prefer smaller pieces, you can slice the apples into matchsticks.
Line the celery sticks up horizontally and slice vertically into thin pieces.
Add the fennel, celery and apple to a large salad bowl with the chopped parsley, mint, nuts and pomegranate seeds.
Toss everything together with the lemon dressing. Adjust salt and pepper as needed.
This salad can be prepared ahead of serving and refrigerated for up to 4 days.