Preheat oven to 400°F (200°C) and line a large baking sheet with parchment paper.
Toss the cubed sweet potatoes with 1 tablespoon of olive oil, 0.5 teaspoon garlic powder, and a pinch of salt on the prepared baking sheet.
Roast sweet potatoes for 25 to 30 minutes, flipping halfway through, until tender and slightly browned.
While potatoes roast, heat the remaining 1 tablespoon of olive oil in a large skillet over medium-high heat.
Add the cubed chicken breast to the skillet and season with the remaining garlic powder, smoked paprika, salt, and pepper.
Sauté chicken for 8 to 10 minutes until the internal temperature reaches 165°F (74°C) and the exterior is golden.
Reduce heat to low and pour the BBQ sauce over the chicken, stirring to coat evenly for 2 minutes.
Divide the fresh spinach across four meal prep containers or bowls.
Top each bowl with equal portions of roasted sweet potatoes and BBQ chicken.
Garnish with sliced red onion and a dollop of Greek yogurt for added protein and creaminess.