Rhubarb Tart & Crème Fraîche
For the crème fraîche:
- 2 cups heavy cream
- ¼ cup buttermilk
For the crust:
- 1 Tbsp honey
- ⅓ cup ice cold water
- 1 egg yolk
- 1 ½ cups all-purpose flour
- 1 Tbsp sugar, plus more for sprinkling
- ½ tsp flake salt, plus more for sprinkling
- ½ stick unsalted butter, chilled and diced
For the tart:
- 8 6-inch stalks of rhubarb, sliced lengthwise, cut into 2-inch pieces
- 1 Tbsp lemon juice
- 1 tsp lemon zest
- 2 Tbsp granulated sugar, plus more for sprinkling
- 1 tsp chopped thyme leaves, plus more for sprinkling
- 1 tsp cornstarch
- 1 whole egg, whisked
- Flake salt, for garnish
- To make the crème fraîche: In a sanitized quart mason jar, combine the cream and buttermilk. Cover the jar tightly with cheesecloth and store it in a cool, dry place for 24 to 30 hours.
- Remove the cheesecloth and cover tightly with a lid.
- Store the crème fraîche in the refrigerator for up to 7 days, or until you’re ready to make the tart.
- To make the crust: Preheat the oven to 375º.
- In a medium bowl whisk together the honey, water, and egg yolk until combined. Set aside.
- In the bowl of a food processor, combine the flour, sugar, and salt and pulse to mix.
- Add the chilled butter and pulse 6 to 7 times just to break up the butter.
- Add the honey mixture to the dry mixture and pulse until a very loose dough has formed.
- Turn the dough out onto a lightly floured surface, and gently knead it into a round shape a few inches thick.
- Wrap the dough in plastic, and chill it in the refrigerator for an hour.
- To make the tart: In a large bowl, toss all of the filling ingredients together — except the egg and flake salt.
- On a lightly floured surface, roll out the dough into a 12-inch round, roughly 1⁄4-inch thick.
- Arrange the rhubarb in one layer on the crust, leaving a 2-inch border around the edge. Note: we arranged ours in a fancy design, but the tart will taste just as delicious if you do something simpler.
- Fold the edge over the filling, leaving the center open.
- Brush the crust with the whisked egg, and sprinkle the crust and filling with a little sugar, thyme, and flake salt.
- Bake for 40 to 45 minutes or until the crust is golden brown. Serve warm or cool with a dollop of crème fraîche.