Preheat your oven to 400°F (200°C).
Cut the acorn squashes in half and scoop out the seeds.
Brush the insides with olive oil and sprinkle with salt and pepper.
Place the squash halves cut-side down on a baking sheet.
Roast in the oven for 25-30 minutes until tender.
In a large bowl, combine cooked quinoa, black beans, diced bell pepper, corn, cumin, salt, and pepper.
Remove the squash from the oven and carefully flip them over.
Fill each half with the quinoa mixture.
Return to the oven and bake for an additional 10-15 minutes.
Garnish with fresh cilantro before serving.