Preheat and prep sheet pan: Preheat the oven to 425°F and line a baking sheet with parchment paper. This keeps the sweet potatoes from sticking while they roast.

Season the sweet potatoes: Toss the diced sweet potatoes with olive oil, chili powder, cumin, smoked paprika, salt, and pepper until evenly coated. Spread them in a single layer on the pan so each piece has room to caramelize.

Roast until golden: Roast for 25 to 30 minutes, flipping halfway through, until the edges turn golden brown and the centers are easily pierced with a fork.

Cook the quinoa: While the sweet potatoes roast, bring the vegetable broth to a boil in a saucepan, add the rinsed quinoa, and reduce to a simmer. Cover and cook for about 15 minutes, until the liquid is absorbed and the grains show a small white ring.

Fluff the quinoa: Remove the quinoa from the heat and let it sit covered for 5 minutes, then fluff with a fork to separate the grains.

Warm the beans and corn: In a skillet over medium heat, warm the black beans and corn together for 3 to 4 minutes, stirring occasionally, until heated through.

Make the dressing: In a small bowl, whisk the Greek yogurt, lime juice, and a pinch of salt until smooth. Add a splash of water if the dressing is too thick to drizzle.

Layer the bowls: Divide the quinoa among four bowls, then top with the roasted sweet potatoes and the warmed black beans and corn.

Add the toppings: Top each bowl with sliced avocado, crumbled cotija cheese, sliced red onion, and chopped cilantro.

Drizzle and serve: Drizzle the lime-yogurt dressing over each bowl right before eating, so the sauce stays bright instead of soaking into the grain.