Combine all sauce ingredients in a medium saucepan. Simmer uncovered over low heat for 15-20 minutes.
Add spinach to sauce. (You may have to do this in a few batches if your pan is small.) Continue simmering until spinach is cooked down and bright green, just a few minutes. Remove from heat and stir in cooked quinoa.
Spoon the sauce mixture into three oven-safe ramekins. Carefully crack two eggs into each ramekin, keeping the yolks intact.
Bake until egg whites are set, about 15 minutes. Remember that the eggs will continue cooking a bit once removed from the oven.
Remove from oven and sprinkle with parmesan cheese, salt and pepper to taste. Serve hot!
Notes
Adapted from Domesticate ME! [Edit: Note that Worcestershire sauce is not vegetarian. For a veg version, sub soy sauce or use vegetarian Worcestershire sauce.]
Recipe by Coffee & Quinoa at https://www.coffeeandquinoa.com/2013/04/baked-eggs-with-tomato-sauce-spinach-quinoa/