Preheat the oven to 200°C and grease a 23cm tart tin with butter.
Roll pastry to 5mm thickness and line the prepared tin.
Cover pastry with parchment, fill with baking beans, and bake for 20-25 minutes.
Remove beans and parchment, brush with beaten egg, and bake for 5 minutes.
Reduce oven temperature to 180°C.
Whisk 8 eggs and cream together then season with salt and pepper.
Arrange asparagus, chicken, and marjoram in the case and pour in the egg mixture.
Scatter cheese on top and bake for 20-25 minutes until set.
Cool on a wire rack before slicing and serving with salad.