Preheat the oven to 350 degrees. Coat a mini baking dish with cooking spray.
Mix the eggs with the milk until well combined then season with dill, sea salt, and freshly cracked pepper, to taste. Place a bit of the feta, spinach, and roasted red pepper into the mini baking dish.
Pour the egg mixture into the baking dish then place the remaining feta, spinach, and roasted red pepper on top.
Place into the oven and bake for 25-30 minutes, or until a tester inserted into the center comes out clean. Remove from the oven and serve immediately. Enjoy.