Start by patting the chicken breasts dry with a paper towel. In a small bowl, mix together the garlic powder, onion powder, smoked paprika, oregano, salt, and pepper. Rub the chicken breasts on all sides with the olive oil, then coat them evenly with the spice mixture.

Preheat your grill or a grill pan over medium-high heat. Once hot, place the chicken breasts on the grill. Cook for about 6 to 8 minutes on each side, or until the internal temperature reaches 165°F (74°C). Remove the chicken from the grill and let it rest on a cutting board for at least 5 minutes before slicing.

While the chicken is grilling, bring a large pot of salted water to a boil. Add the broccoli florets and cook for just 2 to 3 minutes, until bright green and crisp-tender. Immediately drain the broccoli and rinse it under cold water or plunge it into an ice bath to stop the cooking process.

In a medium bowl, combine the Greek yogurt, minced garlic, fresh lemon juice, and dill. Whisk until smooth and well combined. Add water or milk, one tablespoon at a time, until the sauce reaches your desired consistency. Season with salt and pepper to taste.

Slice the rested chicken into strips. To assemble, start with a base of your choice like quinoa or brown rice. Top with sliced grilled chicken and a generous portion of blanched broccoli. Drizzle everything with the creamy garlic sauce. Garnish with fresh parsley and lemon wedges if desired.