Preheat oven to 180 C / Gas 4. Prick bottom and sides of pastry case and bake 10 minutes, until lightly brown; set aside to cool.
Place bacon in a frying pan over medium-high heat and cook until evenly brown. Drain, dice and set aside.
In a bowl, mix eggs, milk, mustard and nutmeg. In a separate bowl, toss bacon with flour to lightly coat. Spread 3/4 bacon mixture and cheese over bottom of pastry case. Pour egg mixture over bacon mixture. Top with remaining bacon mixture.
Bake 1 hour in the preheated oven, or until a fork inserted in the centre comes out clean. Cool 10 minutes before serving.