01 - Preheat the oven to 425°F. Line a large baking sheet with parchment paper.
02 - In a bowl, toss halved baby potatoes with 1 tbsp olive oil, 1/2 tsp paprika, 1/4 tsp salt, and 1/4 tsp pepper. Spread evenly on the baking sheet.
03 - Roast potatoes for 15 minutes.
04 - While potatoes are roasting, combine chicken breasts, 1 tbsp olive oil, remaining paprika, garlic powder, oregano, remaining salt and pepper, and lemon juice. Let marinate for 10 minutes.
05 - Add red bell pepper and red onion to the potatoes. Toss gently, then return to the oven and roast an additional 15 minutes or until potatoes are golden.
06 - Heat a grill pan or skillet over medium-high heat. Grill chicken for 5-6 minutes per side, or until cooked through and juices run clear. Rest chicken for 5 minutes, then slice.
07 - Arrange spinach leaves in bowls. Top with roasted potatoes, grilled chicken slices, roasted peppers and onion, and cherry tomatoes.
08 - Garnish with parsley and serve with lemon wedges, if desired.