Heat a medium saucepan over medium heat and toast the rinsed quinoa for 3 minutes, stirring frequently until it starts to pop slightly.

Add the broth to the quinoa, bring to a boil, then reduce heat to low and cover. Cook for 15 minutes, then remove from heat and let sit covered for 5 more minutes. Fluff with a fork and let cool.

While quinoa cooks, pat salmon fillets dry with paper towels. Mix olive oil, cumin, garlic powder, paprika, salt, and pepper in a small bowl.

Rub the spice mixture all over salmon fillets and let sit at room temperature for 15 minutes.

Preheat grill to medium-high heat (400°F). Clean and oil grill grates well.

Grill salmon for 4-5 minutes on first side without moving. Flip carefully and cook 3-4 minutes more until internal temperature reaches 145°F.

Remove salmon from grill and squeeze fresh lime juice over each fillet immediately.

While salmon rests, whisk together all dressing ingredients in a large bowl.

Add cooled quinoa, cucumber, cherry tomatoes, red onion, cilantro, and mint to the dressing. Toss until well coated.

Taste quinoa salad and adjust seasoning with more lime juice or salt as needed.

Serve grilled salmon over quinoa salad and sprinkle with feta cheese if using. Garnish with extra cilantro and lime wedges.