Preheat oven to 375 degrees F. Line a baking sheet with parchment paper.
Lightly grease an 8 x 8-inch baking dish with olive oil or cooking spray to coat. Toss broccoli florets in olive oil, salt, and pepper. Arrange in a flat layer on the baking sheet.
Roast for 10-12 minutes, or until golden brown and cooked through. While broccoli roasts, combine eggs, milk, and both cheeses in the blender. Blend until combined. Add the dry ingredients and blend.
Pour the mixture into the greased baking pan. Once broccoli is cooked, add the roasted broccoli by carefully dropping the florets into the egg mixture. Bake for 15 minutes or until cooked through in the center. Cut into slices and top with chopped parsley to serve, if desired.