In an oven-safe skillet (cast iron), heat the oil and tomato sauce, over medium heat. Cook for a few minutes until bubbly and slightly reduced. Add the chips a bit at time, tossing with tongs to fully coat in sauce. Continue to toss and cook until the sauce has absorbed. Remove from heat.
In a large bowl, whisk together the eggs, milk, salt and pepper, and add to the skillet over the chilaquiles. Top with the monterey jack cheese and bake for about 20 to 25 minutes, or until puffed and golden brown. Remove from the oven and top with desired garnishes. Cut and serve right away. Enjoy!