- 1/2 cup all purpose flour
- 1/2 cup whole wheat flour
- Pinch of salt
- 4 tablespoons cold unsalted butter
- 2 tablespoons cold milk or cream
- 1 egg, beaten and set aside
- 1 rectangular tart pan with a removable bottom
In a food processor, combine the flours, salt, and butter and pulse until the mixture looks crumbly. With the processor running, add 1 tablespoon of the milk, and if it does not start to form a ball, and another tablespoon. Place the dough onto a sheet of wax paper. Flatten into a disk, and place in the refrigerator for 30 minutes or longer.
Heat the oven to 400 degrees. Place the dough on a lightly floured surface and with your hands, form into a skinny rectangle. Roll the dough out so it is slightly larger than the tart pan, about 1-inch or so on all sides. Carefully place the dough into the pan and press against the sides and bottom discarding any extra. Place the tart pan onto a baking sheet. Place a piece of parchment paper over the dough and fill with dried beans. Bake for 15 minutes. Remove from the oven, discard the paper and beans, prick all over with a fork, brush with the beaten egg, and bake for 5 more minutes. Set aside.
For the filling:
- 1 pound Yukon Gold potatoes, peeled and cut into 2-inch chunks
- 1/3 cup half & half
- 2 tablespoons unsalted butter
- Salt and pepper
- 1/2 a bunch very thin asparagus tips, cut into 3.5-inch lengths
- 1/4 pound white cheddar, grated
- 1 tablespoon chopped chives
Place the potatoes in a pot and cover with water. Place over high heat and bring to a boil, simmering until the potatoes are easily pierced with a knife. Drain and set aside. In the same pot over medium-low heat, add the half & half and butter until melted. Return the potatoes to the pot and mash until fairly smooth. Season to taste with salt and pepper.
In a bowl add the cheddar, chives, and potato mixture and stir together until well-mixed. Spoon into the prepared tart pan and smooth the top. Lightly press the asparagus tips into the top, alternating top to bottom. Turn the oven down to 325 degrees. Place the tart in the oven and bake for 20 minutes. Let cool for 5 minutes before serving.