In a small bowl, combine warm water with sugar, then sprinkle active dry yeast over the top. Allow to sit for 5-10 minutes until frothy.

In a separate bowl, whisk together all-purpose flour and salt. Gradually mix in the yeast mixture and olive oil until a shaggy dough forms.

Transfer the dough to a floured surface and knead for 5-7 minutes until smooth and elastic. Place in an oiled bowl, cover, and let rise for 1-1.5 hours.

In a skillet over medium heat, toast pine nuts for 3-5 minutes until golden and fragrant. Set aside to cool.

In a food processor, combine fresh basil leaves, grated Parmesan cheese, cooled pine nuts, and garlic. Pulse until finely chopped, then drizzle in olive oil while blending.

Preheat your oven to 450°F (232°C) with a pizza stone or baking sheet inside for at least 10-15 minutes.

Once the dough has risen, punch it down and divide into two portions. Roll each out on parchment paper to about ¼ inch thick.

Spread pesto evenly over each flatbread, top with mozzarella cheese, sun-dried tomatoes, olives, and additional Parmesan if desired.

Transfer the assembled flatbread pizzas onto the preheated stone or baking sheet. Bake for 12-15 minutes until golden brown and bubbly.

Remove from oven and let cool slightly. Garnish with fresh basil leaves and red pepper flakes before serving.