The only problem with what's essentially an ooey-gooey Mexican grilled cheese sandwich is that it's often not much more interesting than two tortillas held together with some melted Monterey Jack. Add-ins like chicken and steak taste delicious but can take longer to cook than bang-for-your-buck ingredients like earthy shiitake mushrooms, which are ready in less than five minutes, or inexpensive but filling shrimp, which might just be the quickest-cooking protein on the planet. Even speedier are chicken sausage and smoked turkey. Since they're ready to eat, you can just layer them in with the cheese; as it melts, they'll warm up.
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