Preheat your oven to 180°C (350°F).
Arrange the bacon on a tray lined with non-stick baking paper and bake for about 12 minutes, or until it begins to crisp.
Prepare a 20cm springform cake tin by lining it with two large pieces of non-stick baking paper, ensuring they overlap.
Brush both sides of the tortillas with melted butter.
Sprinkle one tortilla with parmesan cheese, then place the second tortilla on top to create a sandwich.
Put the stacked tortillas into the prepared tin and bake for 5 minutes, or until the tortilla case is lightly golden. Set aside.
In a bowl, whisk together the eggs, milk, cream, Dijon mustard, salt, and pepper.
Stir in the grated cheddar cheese and chives until well combined.
Pour the mixture into the tortilla case and nestle the bacon on top. Bake for 40 minutes or until just cooked but with a slight wobble in the centre. Stand for 10 minutes before serving.