Preheat your oven to 350 degrees Fahrenheit. While the oven is heating, grab a 9 x 13-inch casserole dish and spray it with nonstick cooking spray. This ensures that your casserole comes out easily and the biscuits don’t stick.
In a large skillet, cook 2 pounds of lean ground beef over medium-high heat. Stir it occasionally until there’s no pink left, which should take about 5 to 7 minutes. Be sure to drain off any excess fat to keep the dish from being greasy.
Add 1 cup of diced onion and ½ cup of diced bell pepper to the skillet. Cook for about 3 to 4 minutes until the onion turns translucent. You'll know it’s ready when the onions are soft and fragrant.
Next, stir in 1 packet of taco seasoning, 1 (4-ounce) can of diced green chiles, and 1 (10-ounce) can of Rotel diced tomatoes and green chiles. Cook for another 2 to 3 minutes until everything is heated through and slightly thickened. The mixture should be bubbling gently.
In a small bowl, combine ¾ cup of sour cream, ¾ cup of mayonnaise, and ½ cup of the 2 ½ cups of shredded cheddar cheese. This creamy mixture will add a luscious layer to your casserole.
Open the 1 (16.3-ounce) can of Grands biscuits and remove the biscuits. Press them into the bottom of your prepared casserole dish, stretching and pinching them as necessary to cover the entire base.
Bake the biscuits in the preheated oven for about 12 minutes until they’re lightly golden. This step gives the base a nice, firm foundation for the toppings.
Once the biscuits are done, remove them from the oven and layer the beef mixture evenly over the top. Then, spread the creamy mixture as evenly as possible. The combination of flavors here is what makes the John Wayne Casserole so delicious!
Sprinkle the remaining 2 cups of shredded cheddar cheese over the top. This is where the magic happens as it melts during baking!
Return the casserole to the oven and bake for an additional 30 to 35 minutes. Keep an eye on it until the cheese is fully melted and starts to turn a lovely golden brown. When it’s done, the entire dish should be bubbling and inviting.
Remove from the oven and let it cool slightly before serving. This casserole is best enjoyed warm, straight from the oven!