Roast: Preheat oven to 425 F (218 C). Throw all Filling ingredients in a large bowl and toss to evenly coat. Spread onto a parchment-lined baking sheet and bake for 30 minutes, or until squash is fork-tender.
Sauce: Combine all Sauce ingredients, adding a touch of water to thin into a sauce consistency.
Assemble: Evenly top flatbreads* with roasted fillings, hummus sauce, and arugula.
*Flatbreads too stiff to fold? Stack them onto each other and wrap the whole bundle in a damp paper towel Microwave for 30 seconds, or until they're flexible enough to fold!