01 - In a saucepan, bring quinoa and water (or broth) to a boil. Reduce heat to low, cover, and simmer for 15 minutes or until liquid is absorbed. Remove from heat and let sit, covered, for 5 minutes. Fluff with a fork and set aside to cool.
02 - Preheat a grill or grill pan over medium-high heat. Lightly oil the grates. Grill pineapple rings for 2–3 minutes per side until nicely charred. Remove, cool slightly, and cut into bite-sized pieces.
03 - In a small bowl, whisk together lime zest, lime juice, olive oil, agave nectar, ground cumin, salt, and pepper until well combined.
04 - In a large bowl, combine cooked quinoa, grilled pineapple pieces, cherry tomatoes, cucumber, red onion, cilantro, and jalapeño if using. Pour the dressing over the salad and toss gently to coat evenly.
05 - Taste and adjust seasoning with additional salt, pepper, or lime juice as needed. Serve chilled or at room temperature.