Just about anything goes when it comes to making quesadillas. But when I’m after a meal-worthy option that’s guaranteed to satisfy all the hungry eaters around the table, nothing beats a loaded steak quesadilla. Inspired by fajitas, these quesadillas are packed with thin slices of cumin-rubbed flank steak, charred peppers and onions, and plenty of melty cheese, plus some guac and salsa for topping. Building Blocks These are the four key components of a really good steak quesadilla: Tortillas: Use 10-inch (often labeled “burrito-size”) flour tortillas. They’re big enough to hold all the fillings for loaded, meal-worthy quesadillas. Cheese: Monterey Jack, mild cheddar, or a combination of the two are our top picks for their great meltability. Steak: These quesadillas call for flank or skirt steak that’s seasoned with ground cumin, salt, and pepper and seared on the stovetop, then cut into thin slices. Vegetables: Here we use sliced onion …