Preheat oven to 375 degrees. Line a baking pan with foil. Place naan bread on baking pan and set aside.
Meanwhile, spoon red curry paste into a small saucepan over medium-high heat. Slowly whisk coconutmilk into paste until fully incorporated. Bring to a simmer.
Combine the water and cornstarch in a measuring cup and whisk until completely smooth. Pour into coconutmilk mixture and whisk until thickened and smooth, about 1 or 2 minutes. Set aside and cool slightly.
Divide coconut curry sauce between the two flatbreads, spreading into a thin layer as you would pizza sauce. {You may want to reserve a few tablespoons for garnishing, if desired.} Top with broccoli, zucchini, onion and carrot.
Bake for about 15-20 minutes or until the flatbread begins to brown around the edges and the vegetables are tender-crisp.