Preheat oven to 425°F. Remove puff pastry from fridge and trim to fit baking sheet or pizza stone.
Using a fork, prick around the edges of the puff pastry to create an indentation around the perimeter. Brush edges gently with egg whites.
Quickly layer cheese, prosciutto, sun-dried tomatoes, and basil in the center of the pastry. Drizzle with olive oil and sprinkle flaky salt.
Transfer to oven and bake until golden brown, about 20 minutes.
While baking, mix Manukora honey, red pepper flakes, and apple cider vinegar in a bowl to make the hot honey.
Remove tart from oven once golden and bubbly. Drizzle with hot honey and serve immediately.
Notes
Storage: Best eaten warm the day it's baked while the pastry is still crisp. Leftovers keep in the fridge for a day; reheat in the oven, not the microwave, to bring back some of the crunch.