Preheat a large skillet over medium heat. Add 1 tbsp olive oil into the pan along with the red onion. Saute for 3 minutes to soften, then add the garlic and spinach in. Saute for 1-2 more minutes until the spinach begins to wilt. Remove from heat and pour the cooked vegetables into a large bowl.
Preheat griddle to 350 degrees F, or a large skillet to medium-high heat.
Add the cheddar, quinoa, tuna, panko, sea salt and pepper into the bowl with the vegetables. Using a fork, mix everything together. Once combined, add the 4 eggs in and stir with a fork until the eggs are incorporated.
Add the remaining 1/2 tbsp olive oil to the preheated griddle (if you use a skillet you may need more). Use a 1/4 cup measuring cup to scoop the mixture and place mounds onto griddle. Flatten slightly. Cook for 4 minutes, or until the bottom side is golden. Flip, press down slightly again, then cook for 3 more minutes on the second side, or until both are golden. Remove and enjoy now or later!