- Heat 1 tablespoon of the oil in a heavy nonstick skillet over midium-high heat.
- Add the Onion, garlic, and jalapeño pepper, and saute until soft about 3 minutes.
- Add the mashed beans to the pan and saute, for 1 minute.
- Fold in the spinach, stirring well to incorporate.
- Remove the pan from the heat and allow the mixture to cool.
- Season with the five spice-powder and salt and pepper.
- Place 6 of the tortillas flat on a work surface and divid the bean mixture among them, spreading the filling on top of each tortilla but leaving a 1/2-inch border around the tortilla edges.
- Brush the tortilla edges with beaten egg, then place a second tortilla on top, pressing down to seal.
- Preheat the oven to 200F degrees.
- Place a heavy skillet over medium-high heat.
- Brush tops and bottoms of the tortillas with the remaining oil and cook each one in the hot skillet until light brown, about 2 minutes on each side.
- Keep the finished quesadillas warm in the preheated oven until all of them are cooked.
- Remove the quesadillas from the oven.
- Leave whole or cut into wedges and serve immediately.