Prep your fillings. If using sausage, bacon, or chorizo, cook it first and set aside. Chop any veggies and give them a quick sauté with a little oil and salt until just tender. This prevents watery quesadillas later.

Scramble the eggs gently. Whisk the eggs with a pinch of salt and pepper. Warm a nonstick skillet over medium-low heat with a teaspoon of butter. Pour in the eggs and stir slowly until just set and still glossy. Don’t overcook; they’ll finish in the quesadilla.

Warm the tortillas. Wipe the pan if needed. Add a thin layer of butter or oil. Place one tortilla in the pan over medium heat for 15–20 seconds per side to soften and build a little color.

Layer the fillings. With the tortilla in the pan, sprinkle a thin layer of cheese on half the tortilla. Add eggs, cooked meat, and veggies. Top with spinach, a pinch of chili powder or smoked paprika, and another light sprinkle of cheese. Cheese on both sides acts like glue.

Fold and cook. Fold the empty half over the filling to form a half-moon. Press gently with a spatula. Cook 2–3 minutes per side, until the tortilla is golden and crisp and the cheese is melted.

Repeat with the second tortilla. Add a touch more butter or oil as needed to keep the surface crisp and prevent sticking.

Rest, slice, and serve. Let the quesadilla rest on a cutting board for 1 minute so the cheese sets slightly. Slice into wedges. Serve with salsa, hot sauce, and a dollop of sour cream or Greek yogurt. Add cilantro or avocado if you like.