Adjust rack to top position and preheat oven to 450 degrees. Wash and dry all produce. Peel and dice sweet potato into 1/2-inch pieces. Toss on a baking sheet with a drizzle of oil, salt, and pepper. Roast, tossing halfway through, until browned and tender, 20-25 minutes. Transfer to a medium bowl. Heat broiler to high or oven to 500 degrees.

Meanwhile, core, deseed, and dice poblano. Halve, peel, and dice onion; mince a few pieces until you have 1 TBSP (2 TBSP for 4 servings). Finely chop cilantro leaves and stems. Dice tomato. Trim and finely dice radishes. Quarter lime. Place 1/2 tsp Southwest Spice in a small bowl and set aside (save the rest for cooking your veggies).

Heat a drizzle of oil in a large pan over medium-high heat. Add poblano and diced onion; season with salt and pepper. Cook, stirring, until tender, 5-7 minutes. Once sweet potato is done roasting, add to pan along with remaining Southwest Spice. Cook until fragrant, 1-2 minutes. Turn off heat.

In a second medium bowl, combine radishes, tomato, cilantro, minced onion, juice from 1 lime wedge (2 lime wedges for 4 servings), and large drizzle of olive oil. Season generously with salt and pepper. To bowl with reserved Southwest Spice, add sour cream, a squeeze of lime juice, and a pinch of salt. Stir in water 1 tsp at a time until mixture reaches a drizzling consistency.

Rub one side of each tortilla with a drizzle of oil. Place tortillas, oiled sides down, on baking sheet used for sweet potato. (Use 2 baking sheets for 4 servings.) In a second small bowl, combine cheddar and mozzarella. Sprinkle half the cheese mixture onto one side of each tortilla. Top with veggies, then sprinkle with remaining cheese mixture. Fold tortillas in half to create two quesadillas (four for 4 servings).

Broil or bake quesadillas until golden brown, 1-2 minutes per side. Cut into wedges. Divide quesadillas and salsa between plates. Top quesadillas with crema. Serve with remaining lime wedges on the side.