Prepare for Cooking: Preheat your oven to 425°F (220°C). Place a 12-inch (30 cm) Dutch oven or other large, oven-safe pot over medium-high heat.

Sauté Aromatics: Add the olive oil to the pot. Once shimmering, add the diced onion and chopped jalapeño. Sauté for 4-5 minutes, stirring occasionally, until they begin to soften. Stir in the smoked paprika, ancho chile powder, and oregano and cook for 45 seconds until fragrant. Add the minced garlic and cook for 30 seconds more, stirring constantly.

Toast and Simmer: Add the rinsed quinoa and stir for one minute to lightly toast the grains. Pour in the sodium-free vegetable broth, the drained tomatoes, and the corn. Stir to combine and bring the mixture to a steady simmer.

Cook the Quinoa: Once simmering, reduce the heat to low, cover the pot tightly, and cook for 18-20 minutes, or until all the broth has been absorbed and the quinoa is tender.

Add Fillings and Cheese: Remove the pot from the heat. Gently fold in the rinsed black beans and ¾ cup of the shredded cheese blend until the cheese is melted and everything is evenly distributed.

Bake to Perfection: Smooth the top of the mixture. Sprinkle the remaining ¼ cup of cheese uniformly over the surface. Transfer the uncovered pot to the preheated oven and bake for 10-12 minutes, until the casserole is hot and the cheese is bubbly and golden.

Garnish and Serve: Carefully remove the pot from the oven. Let it rest for 5 minutes before garnishing generously with fresh cilantro and scallions. Serve hot with lime wedges and a dollop of Greek yogurt, if desired.