Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Dice the yellow potato into small half-inch cubes and toss them in a bowl with 0.25 tablespoons of olive oil, dried rosemary, and a pinch of sea salt.
Spread the potatoes in a single layer on one side of the baking sheet and roast for 12 minutes.
While the potatoes are roasting, season the chicken breast and form the ground beef into two small, flat patties or bite-sized chunks.
Season both the chicken and the beef evenly with garlic powder, the remaining sea salt, and black pepper.
Carefully remove the baking sheet from the oven, move the potatoes to one side, and add the chicken and beef to the empty space.
Return the sheet to the oven and roast for an additional 12-15 minutes until the chicken reaches an internal temperature of 165°F.
Steam the broccoli florets in a steamer basket for 5 minutes until vibrant green, then toss with the remaining 0.25 tablespoons of olive oil.
Assemble your meal by placing the warm brown rice in a bowl and topping it with the roasted chicken, beef, golden potatoes, and steamed broccoli.