Preparation
Wash the broccoli and divide into florets. Peel the onions and cut into thin rings.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_1_M.jpg)
Wash the asparagus, peel the bottom half and cut off the woody ends. Cut the asparagus into 5cm pieces.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_2_M.jpg)
Bring the stock to the boil in a saucepan. Add the asparagus and cook, covered, over a medium heat for 5 minutes. Remove and allow to cool.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_3_M.jpg)
Add the onions to the stock, bring to the boil and cook for 2 minutes. Add the broccoli, boil again and cook for 1 minute.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_4_M.jpg)
Pour the Stock through a sieve into a bowl, remove the vegetables and allow to cool.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_5_M.jpg)
Meanwhile, mix the rye flour, flour, baking powder and 1/2 tsp salt in a bowl. Add 5 tbsp cold water and the chilled butter in small pieces, and mix to a smooth dough.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_6_M.jpg)
Roll out about two-thirds of the dough on a floured surface to a 30cm round. Wrap the remaining dough in cling film, and place in the fridge.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_7_M.jpg)
Lightly grease a 28cm tart tin. Line with the rolled out pastry and prick the base several times with a fork. Bake in the preheated oven at 200°C (180°C fan, gas 6) for 10-15 minutes. Remove from the oven and allow to cool slightly.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_8_M.jpg)
Meanwhile, mix the eggs with the sour cream and 100ml of the cooled stock. Season with salt and pepper.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_9_M.jpg)
Take the remaining pastry from the fridge and shape into 2 thin rolls, about 42cm long. Press the rolls, one on top of the other, around the edge of the tart.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_10_M.jpg)
Add the asparagus, broccoli and onions to the tart tin and pour in the egg mixture. Bake the tart in a preheated oven at 200°C (180°C fan, gas 6) for 30 minutes. Season with pepper and serve.
![](https://blog.liebherr.com/wp-content/lh-recipe-images/000606/000606_step_11_M.jpg)