4 (10-inch) flour tortillas
1 cup chopped frittata or scrambled eggs
Mexican hot sauce (optional)
1 cup shredded cheese, such as cheddar or Monterey Jack
Place a large frying pan or griddle over medium heat. Meanwhile, assemble the quesadillas.
Stack the tortillas on a microwave-safe plate and cover with a damp paper towel. Microwave until soft and pliable, about 30 seconds.
Place the tortillas on a work surface. Divide the eggs onto the tortillas, spreading into an even layer but leaving a 1 1/2-inch border. Sprinkle with hot sauce, if using. Divide the cheese over the eggs.
To fold the quesadillas, fold the top of the tortilla down over the filling to the center. Holding that piece down and working clockwise, continue folding the rest of the tortilla towards the middle until the filling is completely covered (you will have about 5 folds). Carefully flip the quesadilla over and repeat with the remaining tortillas.
Place the quesadillas, folded-side down, in the heated pan or griddle, as many as will fit in a single layer. Cook until browned and the cheese is melted, 4 to 5 minutes on each side. Repeat as needed until all the quesadillas are cooked. If not serving immediately, let cool completely and wrap each quesadilla tightly in foil. Refrigerate or freeze in a resealable plastic bag.
Reheating instructions: Reheat uncovered in a 325°F regular or toaster oven until warmed through, about 20 minutes if refrigerated or about 30 minutes if frozen. You can also microwave on a paper towel on high for 1 to 2 minutes.