My career in food began 20 years ago, when I volunteered to assist with cooking classes at Sur la Table. It was just a few classes here and there based on my interests, which I already knew was baking at that point. One of the recipes I remember to this day is this heirloom tomato tart. I can still recall my reaction I had when I ate it. Absolutely delicious. Flaky crust, subtle tartness from the Dijon mustard and the juiciest tomatoes.
Keep the mustard layer super thin, just to cover the surface of the dough. Anything more and it will be too overpowering. The mustard and cheese layers will act as a barrier to prevent the crust from getting soggy, but it still helps to place the tomatoes on a towel to soak up the excess moisture.
If you want to try a different take on the savory galette, try my Heirloom Tomato Galette with Goat Cheese and Parmesan-Pepper Crust.
Heirloom Tomato Galette with Gruyere
Adapted from Karen Bowman
Ingredients:
1 1/4 cup plus 2 tablespoons (155 g) all purpose flour
3/4 teaspoon kosher salt
1 teaspoon sugar
4 ounces (113 g) cold, unsalted butter, 1″ cubes
5-6 tablespoons cold water
16 ounces or about 4 medium to large heirloom tomatoes
3 tablespoons Dijon mustard
6 ounces (170 g) Gruyère cheese, shredded
Freshly ground pepper, to garnish
1/2 teaspoon fresh thyme, optional
1 egg, lightly beaten to egg wash
Flake salt, to garnish
Directions:
In a food processor, add the flour, salt and sugar. Pulse a few times to combine. Add the cubed butter and pulse until broken up into the size of small peas. Drizzle in a tablespoon of water at a time, and pulse, until the dough just comes together. Test by squeezing a small portion with the palm of your hand. If still dry, add additional tablespoons until moist. Place the dough onto a work surface and form into a round disc. Place in plastic wrap and chill for 1 hour.
Preheat the oven to 425°F with racks on the middle and lower third of the oven. Line a half sheet pan with parchment for the galette. Line a second sheet pan with paper towels.
Meanwhile, slice the tomatoes 1/3″ thick and place onto the towel-lined sheet pan. This will help absorb the moisture and prevent a soggy galette. Set aside.
Remove the dough from the fridge. If the dough is a bit stiff, let it sit out at room temperature for 5-10 minutes, until pliable enough to roll out. Roll out into a circle, 1/4″ thick and approximately 12-13″ diameter. Transfer to the parchment-lined sheet pan.
Spread a thin layer of mustard in the middle, leaving a 2″ border. Scatter the Gruyere evenly over the mustard. Arrange the tomato slices on top of the cheese, overlapping slightly. Fold the edges of the dough up over the tomatoes. Sprinkle pepper on the tomatoes. Top with fresh thyme if you wish. Brush the dough border with egg wash. Place the sheet pan in the fridge for 10 minutes just to let the firm up.
Bake for 25 minutes. During the last 10 minutes, if the crust is not quite golden, move the sheet pan to the middle rack to finish baking, until golden brown.
Place the galette on a cooling rack. Sprinkle the tomatoes with flake salt. Let the galette rest about 1 hour before serving. The galette tastes best slightly warm or at room temperature, when the filling has had time to settle. Enjoy with lightly dressed greens for a summer brunch. Leftovers can be reheated on the lower rack of an oven at 300°F for about 5 minutes or until the bottom crust is crisp.
Serves 6.