Step 1: Prepare & Preheat

• If you are planning to bake the casserole immediately, preheat your oven to 350°F (175°C). This ensures the oven is at the correct temperature when the casserole is ready to bake, promoting even cooking.

Step 2: Cook the Chorizo

• Heat a large nonstick skillet over medium-high heat. Nonstick is crucial for preventing the chorizo and vegetables from sticking and burning.
• Add the chorizo to the hot skillet. Using the back of a wooden spoon, break the chorizo apart into small crumbles. This helps it cook evenly and integrate better into the casserole.
• Cook the chorizo until it is browned and cooked through, rendering its fat. This typically takes about 5-7 minutes.
• Using a slotted spoon, transfer the cooked chorizo to a small bowl, leaving the rendered fat in the skillet. The rendered chorizo fat is packed with flavor and will be used to cook the vegetables.

Step 3: Sauté the Vegetables

• Reduce the heat in the skillet to medium. Ensure the heat isn’t too high to prevent burning the vegetables in the rendered chorizo fat.
• Add the diced sweet potatoes, onions, and green peppers to the skillet with the rendered sausage fat.
• Sprinkle half of the kosher salt (½ teaspoon) and half of the black pepper (¼ teaspoon) over the vegetables. Seasoning at this stage helps to draw out moisture and enhance the flavor of the vegetables as they cook.
• Stir to combine the vegetables and seasonings, ensuring they are coated in the flavorful chorizo fat.
• Cover the skillet with a lid. This helps to steam the vegetables and speed up the cooking process, ensuring they become tender.
• Cook for 10-12 minutes, stirring occasionally, until the sweet potatoes start to brown and are tender when pierced with a fork. Keep an eye on the vegetables to prevent burning, adjusting the heat as needed.

Step 4: Combine Chorizo, Vegetables, and Chiles

• Remove the skillet from the heat. This prevents further cooking and allows the mixture to cool slightly before adding the cheese and eggs.
• Stir in the cooked chorizo and chopped Hatch chiles into the vegetable mixture. Combine thoroughly to distribute the flavors evenly throughout the mixture. Set aside to cool slightly while you prepare the cheese and egg mixture.

Step 5: Prepare the Cheese Mixture

• In a separate medium bowl, toss together the shredded Monterey Jack cheese and shredded cheddar cheese. Mixing the cheeses beforehand ensures an even distribution of both flavors and textures in the casserole.
• Set aside the cheese mixture.

Step 6: Prepare the Egg Mixture

• In a medium bowl (you can reuse the cheese bowl after emptying it), combine the eggs, milk, remaining salt (½ teaspoon), and remaining pepper (¼ teaspoon).
• Whisk the ingredients together vigorously until well combined and slightly frothy. Whisking incorporates air into the eggs, resulting in a lighter and fluffier casserole.

Step 7: Assemble the Casserole

• Spray a 1 ½ to 2 quart casserole dish with vegetable cooking spray. This prevents the casserole from sticking to the dish and makes for easier serving and cleanup.
• Transfer the chorizo and vegetable mixture to the prepared casserole dish, spreading it evenly across the bottom.
• Top the chorizo mixture with ¾ of the cheese mixture, reserving the remaining ¼ for topping. Distribute the cheese evenly over the chorizo and vegetables.
• Pour the egg mixture evenly over the cheese and sausage layer.
• Gently use a wooden spoon or spatula to lightly adjust the ingredients, ensuring they are balanced and somewhat combined. Avoid overmixing, but make sure the egg mixture is distributed throughout the casserole.

Step 8: Bake the Casserole (or Make Ahead)

• To Cook Now: Sprinkle the top of the casserole evenly with the remaining ¼ of the cheese mixture.
• Bake in the preheated oven for 30-45 minutes, or until a cake tester or toothpick inserted into the center of the casserole comes out clean. The baking time may vary depending on your oven and the depth of the casserole. The top should be golden brown and the center should be set.
• For Make Ahead: If you are making the casserole ahead of time, stop at Step 7. Cover the assembled casserole dish tightly with plastic wrap and refrigerate for up to 24 hours. Store the remaining cheese mixture separately in a resealable bag or container in the refrigerator.
• When ready to bake from refrigerated, remove the casserole from the refrigerator about 45 minutes before baking to allow it to come closer to room temperature. This helps ensure even baking and prevents the dish from cracking due to a sudden temperature change. Preheat the oven to 350°F (175°C). Sprinkle the reserved cheese over the top and bake as directed in Step 8 (30-45 minutes).

Step 9: Rest and Serve

• Once baked, remove the casserole from the oven and let it rest for 10 minutes before serving. Resting allows the casserole to set further and makes it easier to slice and serve.
• Serve warm and enjoy!