Preheat oven to 220°C. Lightly grease a 20cm loose bottom flan tin. Cook bacon in a non-stick frying pan for 3 mins until golden. Transfer to a plate.
Heat oil in a small frying pan and cook onion until soft. Add spinach and cook until liquid has evaporated. Transfer to a bowl and stir in cream. Season with black pepper. Cool.
Line prepared tin with pastry, rolling in the excess pastry. Spread spinach mixture over base. Crack the eggs over the spinach and scatter the bacon over the top. Bake for 35 minutes until filling is set. Cut into wedges and serve.