Preheat your oven to 400°F and line a large baking sheet with parchment paper for easy cleanup.
Rinse the quinoa under cold water then combine it with 0.5 cup of water in a small saucepan, bringing it to a boil before covering and simmering for 15 minutes.
Dice the sweet potato into half-inch cubes and chop the broccoli into bite-sized florets.
Place the chicken breast, sweet potato cubes, and broccoli florets onto the baking sheet in a single layer.
Drizzle the olive oil over everything and season evenly with the sea salt, black pepper, garlic powder, and smoked paprika.
Roast in the oven for 20 to 25 minutes until the chicken is cooked through and the vegetables are tender with slightly browned edges.
While roasting, whisk together the tahini and lemon juice in a small ramekin, adding a teaspoon of warm water if needed to reach a pourable consistency.
Slice the roasted chicken into strips and assemble your bowl by layering the quinoa, vegetables, and chicken before finishing with the tahini drizzle.