Preheat your oven to 400°F (200°C). Line a large rimmed baking sheet with parchment paper for easier cleanup.
In a large bowl, toss the cubed chicken with olive oil, salt, pepper, and paprika until evenly coated.
Place the seasoned chicken, broccoli florets, chopped bell pepper, onion, and halved baby potatoes onto the prepared baking sheet. Spread everything into a single layer.
Bake for 15 minutes.
While the chicken and vegetables bake, prepare the garlic butter sauce. In a small saucepan over medium heat, melt the butter. Add the minced garlic and Italian herbs. Cook for 1 minute until fragrant, stirring constantly. Remove from heat and stir in the lemon juice.
Carefully remove the baking sheet from the oven. Drizzle the garlic butter mixture evenly over the chicken and vegetables. Toss gently right on the pan to coat everything.
Return the pan to the oven and bake for another 10 to 15 minutes, or until the chicken is cooked through (internal temperature reaches 165°F or 74°C) and the vegetables are tender.
Remove from the oven, sprinkle with fresh parsley, and serve immediately directly from the pan.
Notes
For crispier potatoes, toss them with a little extra olive oil before adding them to the pan.
You can substitute the vegetables with zucchini, carrots, or mushrooms based on what you have available.
If you prefer a richer sauce, add 1 tablespoon of grated Parmesan cheese to the butter mixture just before drizzling.