Preheat oven to 400°F and allow it to fully heat before cooking.

Wash and dry all vegetables. Cut broccoli into small florets, slice bell peppers into strips, and cut potatoes into even pieces for uniform cooking.

Pat chicken breasts dry with a paper towel. If needed, pound them lightly so they are even in thickness.

Place chicken breasts on a large sheet pan. Add all prepared vegetables around the chicken in a single layer.

Drizzle olive oil evenly over chicken and vegetables, making sure everything is lightly coated.

Sprinkle garlic powder, paprika, oregano, salt, and pepper over the entire pan. Toss vegetables gently and rub seasoning onto chicken for even flavor.

Spread everything out so there is space between pieces. This helps achieve a roasted texture.

Bake for 25 to 30 minutes. Flip the chicken and stir vegetables halfway through cooking for even browning.

Check that chicken reaches an internal temperature of 165°F and vegetables are tender with slightly crispy edges.

Remove from oven and let rest for a few minutes. Drizzle lemon juice over the top before serving.