Preheat your oven to 400°F and line a small baking sheet with parchment paper for easy cleanup.
Dice the potato into 1/2-inch cubes and toss them on the baking sheet with 1 teaspoon of olive oil, garlic powder, and a pinch of salt and pepper.
Roast the potatoes for 18-20 minutes, flipping halfway through, until they are golden brown and crispy on the outside.
While the potatoes roast, heat the remaining 1 teaspoon of olive oil in a large non-stick skillet over medium-high heat.
Add the diced onion and sliced mushrooms to the skillet, sautéing for 5-6 minutes until the onions are translucent and the mushrooms have released their moisture.
Add the ground chicken breast to the skillet, breaking it into small crumbles with a wooden spoon, and season with the dried oregano and remaining salt and pepper.
Cook the chicken for 5-7 minutes until fully cooked through and no longer pink.
Stir in the halved cherry tomatoes and cook for 2 minutes until they just begin to soften and blister.
Add the fresh baby spinach to the pan and toss for 30-60 seconds until the leaves are just wilted.
Remove the roasted potatoes from the oven and fold them into the chicken and vegetable mixture before serving in a shallow bowl.