Combine the rinsed quinoa, broth, cumin, smoked paprika, and salt in a medium saucepan over medium-high heat. Bring it to a boil, then reduce the heat to low, cover, and let it simmer. It usually takes about 12 to 15 minutes for the liquid to fully absorb and the quinoa to turn tender and fluffy.
While the quinoa cooks, pat the shrimp dry and toss them with olive oil, garlic powder, smoked paprika, chili powder, salt, and pepper. Heat a large skillet over medium-high heat and add the shrimp in a single layer. Cook for about 2 to 3 minutes per side, until they turn pink and slightly golden at the edges.
In a small bowl, whisk together the Greek yogurt, lime juice, chopped cilantro, and minced garlic. Add water a tablespoon at a time until the sauce reaches a consistency you can easily drizzle. Taste it and adjust the lime or salt if it needs a little more brightness.
Divide the warm quinoa among four bowls as your base layer. Top each one with baby spinach, cherry tomatoes, sliced avocado, and red onion, arranging them in sections so the colors stand out. Finish with a handful of feta cheese for a salty contrast to the other toppings.
Place a portion of the seared shrimp on top of each bowl while it's still warm. Drizzle the cilantro-lime sauce generously over the top, letting it soak slightly into the quinoa. Serve right away while the shrimp is still hot and the veggies are crisp.