Preheat the oven to 425°F (220°C).
In a large bowl, toss the diced sweet potatoes with olive oil, smoked paprika, garlic powder, cumin, 1/4 teaspoon salt, and black pepper until evenly coated.
Spread the sweet potatoes in a single layer on a baking sheet lined with parchment paper.
Roast the sweet potatoes in the preheated oven for 20-25 minutes, stirring halfway through, until tender and lightly browned.
While the sweet potatoes roast, heat a large skillet over medium-high heat.
Add the ground beef to the skillet and cook, breaking it apart with a spatula, until browned and cooked through, about 7-8 minutes.
Season the beef with the remaining 1/4 teaspoon salt and adjust pepper to taste. Remove from heat.
In a large bowl, combine the cooked quinoa, chopped baby spinach, cherry tomatoes, and red onion.
Add the roasted sweet potatoes and cooked ground beef to the quinoa mixture and gently toss to combine.
In a small bowl, mix the Greek yogurt, chopped cilantro, and lime juice to create a sauce.
Divide the beef and sweet potato mixture evenly into four bowls.
Top each bowl with a dollop of the cilantro lime Greek yogurt sauce.
Serve immediately.