Pre-heat the oven to 400°F (200°C). Line a sheet pan or roasting pan with parchment paper.
Cut the squashes in half across the "equator", scrape out and discard the seeds and fibers. Cut a little bit off the pointy end so the squash will sit upright for presentation.
Spread 1 Tsp of olive oil in the cavity of each squash half and sprinkle lightly with kosher or sea salt. Place the prepared squash halves, cut side down on the sheet pan and roast until tender - about 30-35 minutes. The point of a paring knife should slide easily through the flesh.
While the squash roasts heat 1 1/2 Tbs of olive oil in a medium pot over medium heat. Add the sliced shallots and stir for a minute or two until they begin to soften. Add the mushrooms which should be chopped about the size of the garbanzo beans. Season with salt and cook, stirring occasionally for 5-6 minutes or until the mushrooms are soft and reduced a bit. They will give off some of their moisture and as that liquid evaporates it will concentrate the mushroom flavor.
Stir in the curry powder and orange zest. Add the stock or water to the pot along with the quinoa. Increase the heat to high and bring the stock to a boil. Reduce the heat, cover the pot and simmer until all the liquid is absorbed and the quinoa is fully cooked and tender, about 15-20 minutes.
About 5 minutes before the quinoa is done and there is still some liquid in the pot, add the garbanzo beans to warm through. When the quinoa is cooked and all the liquid is absorbed, remove the pot from the heat and stir in the mint and pepitas (pumpkin seeds). Check for seasoning and adjust accordingly.
When the squashes are cooked and tender, place one half on each plate, cut side up, fill the "bowl" with the quinoa mixture and serve. Garnish with a mint sprig and a drizzle of olive oil.