In a medium-sized pot over medium heat add the olive oil and quinoa. Stir to allow the quinoa to brown. Add the garlic powder, cumin, and chile powder. Stir to combine. Add the water and bring to a boil. Once the quinoa is boiling, cover and reduce the heat to simmer. Cook for 15 minutes.
Add the black beans and corn and stir to combine. Simmer for another 5 minutes. Taste and adjust seasoning to your preference, adding salt and pepper if needed. Remove from the heat and allow to completely cool.
Place quinoa mixture in the middle of a large platter. Surround the quinoa mixture with the tomatoes, red onions, the white parts of the green onions, bell peppers, and avocado slices. Top with the pepitas and Garlic Tonnino Tuna. Sprinkle with the crumbled Queso Fresca.
Drizzle liberally with the Creamy Roasted Salsa Dressing.
Preheat a grill or oven to 425℉. Place the poblano pepper, jalapeño pepper, red onion, tomatoes, and garlic on a baking pan. Drizzle with olive oil. Roast for 20 minutes until the vegetables are softened and the skin on the peppers becomes blistered. Remove and all the vegetables to cool.
Peel the skin from the peppers and deseed them. Place all of the vegetables in a blender and process until smooth. (You should have about 1 cup of roasted vegetable mixture.)
Place the roasted vegetable mixture in a medium-sized bowl and add the sour cream. Truvia or sugar, and lime juice. Whisk to combine. Season with salt and pepper to taste.