Preheat your oven to 200°C (400°F) and line a baking sheet with parchment paper.
Grate the potatoes and zucchini using a box grater.
In a large bowl, combine the flour, water, salt, and pepper. Add the grated vegetables and mix until they are well coated.
Spread the mixture evenly onto the prepared baking sheet. Use a spatula to press it down firmly, forming a flat and cohesive layer.
Bake for 25-30 minutes, until the edges turn golden and crisp. For extra crispiness, optionally brush the top with olive oil before baking.
Allow the baked flatbread to cool, then evenly spread the cream cheese over the entire surface.
Top with arugula, caramelized onions, and finely chopped sun-dried tomatoes. Drizzle with balsamic cream or glaze.
Starting at one short edge, roll the flatbread tightly into a log, using the parchment paper to help guide the roll.
Slice the rolled flatbread into 1-2 inch pinwheels and serve as a colorful appetizer or snack.