Start by preheating your oven to 375°F (190°C). Slice your acorn squash in half horizontally, then scoop out the seeds and stringy bits from the center. Brush the cut sides of the squash with olive oil and sprinkle with salt and pepper. Place the squash cut side down on a baking sheet lined with parchment paper. Roast these for about 25-30 minutes, or until they’re tender but still hold their shape.
While the squash is roasting, prepare the quinoa. Rinse and drain it first, then bring your broth to a simmer in a saucepan. Add the quinoa, reduce the heat, and cover the pan. Cook for 15-20 minutes until the quinoa absorbs all the liquid. Fluff it with a fork before setting it aside.
Heat olive oil in a skillet over medium heat. Fry the chopped onion and garlic first until they’re fragrant. Toss in the red bell pepper and your greens (spinach or kale), and sauté until they soften. Mix in the cooked quinoa, cranberries, nuts, thyme, salt, and pepper. For a creamy, tangy kick, fold in some feta cheese if you like.
Take your roasted squash and turn them cut side up. Scoop the stuffing into each half, pressing it gently into place. Return the stuffed squash to the oven for another 10-15 minutes, or until everything is warmed through and golden on top.