Preheat your air fryer to 350°F (175°C) for about 5 minutes.
In a large bowl, combine the cubed bread, shredded cheese, and diced vegetables. Toss them together until well mixed.
In a separate bowl, whisk together the eggs, milk, dried herbs, salt, and pepper until well combined.
Pour the egg mixture over the bread and vegetable mixture. Gently stir until all the ingredients are evenly coated and the bread is soaked in the mixture.
Lightly grease the air fryer basket with cooking spray or oil to prevent sticking.
Transfer the mixture to an oven-safe dish or a suitable-sized baking pan that fits in your air fryer basket. Spread it out evenly.
Place the dish in the preheated air fryer basket.
Air fry the casserole at 350°F (175°C) for 20-25 minutes or until the top is golden brown and the eggs are set. You can check the doneness by inserting a toothpick in the center; it should come out clean.
Once cooked, remove the casserole from the air fryer and let it cool for a few minutes.
Slice into servings and serve warm. You can garnish with additional fresh herbs, if desired.
Enjoy your delicious vegetarian air fryer breakfast casserole!