Heat oven to 400°F. Heat 1½ tsp. oil in 10” oven-proof, non-stick skillet over medium heat. Add onions and garlic. Cook, stirring occasionally, until onions are soft and translucent, about 10 minutes; transfer to medium bowl. Wipe out pan and set aside.
Add spinach, quinoa and cream cheese to bowl with onion mixture, stirring until ingredients are well distributed. In separate medium bowl, using fork, whisk together eggs, cheddar cheese and Adobo. Pour egg mixture over quinoa mixture; stir until thoroughly combined.
Heat remaining oil in same skillet over medium heat. Pour quinoa mixture into skillet, pressing with spatula into an even layer. Cook until bottom of quinoa is golden brown. Transfer skillet to oven. Cook until quiche is cooked through (thin knife inserted into center of quiche comes out clean) and top of quinoa is light golden brown, 15-20 minutes.
Carefully invert quiche onto serving dish; cut into wedges. Serve warm or at room temperature.