Cook the quinoa and rice according to the package directions. Prepare a standard muffin pan with nonstick baking spray. Preheat the oven to 350ºF.
In a large bowl, combine the cooked quinoa and rice with the eggs, onions, cheese, garlic, basil, tomatoes, chili powder, salt, and pepper. Mix well to combine. Transfer the mixture to the prepared muffin pan. Using a tablespoon, fill each muffin cup to the top. Using a spatula, press down on the mixture to create a flat surface.
Bake for 20 minutes or until golden brown. Remove from the oven and set aside to cool for 15 minutes. Using a teaspoon, gently remove the rice and quinoa snacks from the muffin cups.
Transfer to a serving platter. Serve with a sprinkle of fresh chives and a side of tomato sauce for dipping.