When I cook or bake, I follow three principals: the food should look good; the food should taste good; and the food should be good for you. This savory leek and kale tart with the sweet potato crust fits the bill. For the vegan version of this recipe, you can view here at One Green Planet. Below is how to make it the vegetarian way and bon appétit!

Leek and kale tart with sweet potato crust

Serves 6-8

Level: moderate

Ingredients

Crust

•  1-2 baked sweet potatoes with skin (enough to yield 1 heaping cup mashed sweet potatoes)
• 1 cup white whole wheat flour *
• 1/4 cup warm water (or a bit more, if need be)
• 3 tablespoons (tbsp) omega-3 vegetable oil
• 2 tbsps chia seeds, grounded in a small coffee grinder (after grinding, it doubles to 4 tbsps)
• 1 teaspoon (tsp) baking powder
• Pinch of salt

Vegetables

• 4 big leeks, split lengthwise, cleaned and chopped into 1/4 inch-thick slices
• A little water (2 tbsps)
• 1 cup firmly packed kale, chopped very fine
• 1 tbsp fresh dill weed
• 1 tsp dried thyme
• Salt and ground pepper to taste

Custard

• 3 eggs
• 1/2 cup natural Greek yoghurt (reduced-fat; no added sugars)
• Pinch of cayenne
• 2 tbsps green chives, finely chopped
• 3 tbsps parmesan cheese, finely grated

*I cannot find white whole wheat flour in Switzerland or nearby France. Until I do, for this recipe, I mix 1/2 cup unbleached white flour and 1/2 cup whole wheat pastry flour. If someone has found this type of flour in this part of the world, please let me know in the comment section. Thanks. 

Procedure

Baking sweet potatoes this way is the best way and the skins peel off easily. See picture below:

Preheat oven to 200°C / 400°F. Prick the potatoes a few times with the tip of a knife (this helps to remove the skin) and put them directly on a grilling rack with a pan underneath to catch any syrup that may drip. Lower the oven rack to a low position so that the potatoes on the grilling rack are in the middle of the oven. Put them straight into the oven. Depending on size, sweet potatoes are done in about 45 minutes to an hour. A fork should easily pierce through them and syrup should ooze from the slits. Let cool, remove the skins and mash. Measure one heaping cup of mashed sweet potatoes.

Keep oven heated at 200°C/400°F. Grease and flour a 9 to 10-inch (23-26 cm) quiche or pie pan.

For the crust, put all crust ingredients into a food processor and process until smooth and mixed. The mixture will be sticky. Wet your hands with cold water and take the mixture out of the processor with your hands or you can use a spatula. With cold wet fingers, spread and press the mixture evenly on the bottom and sides of the pan. I also use a stainless steel butter knife to spread the dough. Put the prepared pan in fridge.

For the vegetables, in a medium skillet over medium heat add the leeks and a little water. Cover and cook until the leeks are very soft, reducing the heat as they cook, about 20 minutes. Stir this from time to time. Add the kale, dill weed, thyme, salt and pepper. Stir and cook on low heat with cover on for another 3 minutes.

For the custard, whisk in a bowl until well combined the eggs, yoghurt, cayenne, chives and parmesan cheese. When leeks and kale are done, with a slotted spoon to drain any extra liquid, add the veggies to the custard. Mix this well and transfer to the prepared crust. Spread evenly and bake in preheated oven until golden and the custard is set, 30 minutes. Let rest for 10 minutes to settle, then cut into wedges and serve. Store covered in fridge. It reheats well the next day and can be enjoyed cold.