Grilled Feta Spinach Flatbreads with Parsley Sauce

Steps

1. In a large bowl, whisk the bread flour, whole wheat flour, instant yeast, sugar and 8 g of the salt.
2. Add the lukewarm water and 15 g of the olive oil; stir into a shaggy dough. This is about 68% hydration and 2% salt.
3. Knead 8–10 minutes until smooth and elastic. Cover and rise at about 75°F (24°C) for 1 to 1½ hours, until doubled in size.
4. Meanwhile make the herb sauce: in a blender or food processor, blend the parsley, basil, 6 g of the minced garlic, the lemon juice, 35 g of the olive oil, 15 g of the Parmesan and the remaining 1 g of salt until loose and spreadable. Set aside.
5. Warm the remaining 10 g of olive oil in a large skillet over medium heat, add the remaining 12 g of garlic for 30 seconds, then add the spinach and cook until just wilted, about 2 minutes. Transfer to a sieve, press out the liquid and let cool.
6. Punch down the dough, divide it in half, shape each into a ball and rest covered 15 minutes, until it springs back slowly when poked.
7. Heat the grill to medium-high, about 450–500°F (230–260°C), and oil the grates lightly with a paper towel.
8. Stretch each ball into a rough 11-inch oval on a floured board. Lay one on the grill, cover and cook 2–3 minutes until puffed with grill marks underneath, then flip onto a sheet pan, grilled side up. Repeat with the second.
9. Spread half the herb sauce on each grilled side, then top each with half the spinach, half the mozzarella, half the feta, half the remaining 25 g of Parmesan and a pinch of the red pepper flakes.
10. Return to the grill over medium heat, cover and cook 3–4 minutes until the bottoms are crisp and charred in spots and the cheese melts; the crust should reach about 200°F (93°C) in the center.
11. Slide onto a rack and cool 3 minutes, then cut each flatbread into 6 slices.