Technical Stages :

• Peel and wash the vegetables.
• Coarsely dice the potatoes and turnips. Slice the white part of the leeks.
• Keep the green part aside in case you'd need it for anything else.
• Boil the potatoes and turnips (start in cold salted water) for 15 minutes.
• Sweat the leeks with half the butter.
• When tender, puree them along with the drained cooked potatoes and turnips. Transfer into a pot, add the butter and cook for 10 minutes over medium heat, frequently stirring.
• Add the cream and keep warm. Warm up the croustades in the oven and garnish them with the mashed vegetables. Serve immediately.
• Note :
• You can buy ready-for-use croustades in many stores. However, I recommend you make your own by rolling out puff pastry and cutting 7x7cm-large squares. Glaze with egg yolk and bake in a warm oven.