In a large bowl, whisk the first 6 ingredients. Add pumpkin, 1 tablespoon oil and water; stir until mixture resembles coarse crumbs. Turn onto a lightly floured surface; knead 8-10 times, forming a soft dough. Cover and let rest 15 minutes.
Divide dough into 4 pieces. On a lightly floured surface, roll each piece into a 6-in. circle. Brush flatbreads on both sides with remaining 2 teaspoons oil. Heat a large skillet over medium-high heat. Working in batches, cook flatbreads until golden brown, 1-2 minutes on each side. Serve warm and if desired, top with fresh thyme and rosemary and serve with tzatziki sauce.