1Preheat oven to 400°F (200°C). On a large baking sheet, combine the diced sweet potatoes, bell peppers, and red onion. Drizzle with olive oil, then sprinkle with chili powder, ground cumin, smoked paprika, garlic powder, salt, and black pepper. Toss to coat evenly and spread in a single layer.

2Roast vegetables for 25-30 minutes, tossing halfway, until tender and lightly caramelized. Remove from oven and set aside.

3While vegetables roast, combine the rinsed black beans, enchilada sauce, and frozen corn (if using) in a small saucepan over medium heat. Simmer gently for 5-7 minutes, stirring occasionally, until heated through and flavors have melded. Remove from heat.

4Prepare the avocado-lime crema: In a food processor or blender, combine the avocado flesh, chopped cilantro, lime juice, sour cream (or Greek yogurt), a pinch of salt, and cayenne pepper (if desired). Blend until completely smooth and creamy. If too thick, add a tablespoon or two of water to reach desired consistency.

5To assemble the bowls, divide the shredded romaine lettuce among four serving bowls. Top evenly with the roasted vegetables and the warm black bean mixture.

6Drizzle generously with the fresh avocado-lime crema. Garnish with additional fresh cilantro and crunchy tortilla strips or crushed tortilla chips before serving.