Place a small ungreased skillet over medium heat. Add the pepitas and cook for 3 to 4 minutes, stirring frequently, until they become fragrant, lightly browned, and begin to pop. Transfer them to a plate and allow them to cool so they remain crisp.
Combine the rinsed quinoa, water, garlic powder, cumin, smoked paprika, and salt in a medium saucepan. Bring the mixture to a boil over medium-high heat, then lower the heat, cover the pan, and simmer for 15 minutes. Take the saucepan off the heat and let the quinoa stand, still covered, for an additional 5 minutes. Fluff it with a fork, then spread it across a plate or sheet pan until it reaches room temperature.
While the quinoa is cooking, prepare the produce. Halve the tomatoes, finely dice the red bell pepper, red onion, and jalapeño, thaw the corn, and chop the cilantro. Drain and rinse the black beans thoroughly.
In a small bowl or jar, combine the oil, lime juice, agave or maple syrup, smoked paprika, and kosher salt. Whisk or shake until the dressing is smooth and fully blended. Adjust the amount of lime juice as desired.
Add the cooled quinoa to a large mixing bowl with the black beans, tomatoes, corn, bell pepper, red onion, jalapeño, and cilantro. Toss gently to distribute the ingredients evenly. Pour the dressing over the salad and toss again until everything is lightly coated.
Just before serving, carefully fold in the diced avocado to keep the pieces intact. Sprinkle the toasted pepitas over the top. Taste once more, then brighten with an additional squeeze of lime or a small pinch of salt as needed.