Bite into this crisp, buttery crust, topped with chicken, tomatoes, Gruyère seasoned with fresh herbs and enjoy the amazing taste. At last, here’s a crust that you can pick up eat with your hands, even though it’s gluten-free. The secret to keeping the crust from getting soggy is to sprinkle potato starch over the dough so that it absorbs the extra moisture from the tomatoes. If you change the fillings, blot off any extra moisture before you layer them. Tomato sauce and other watery fillings won’t work with this dough, but any sliced meat or cheese combination can be substituted with great results. Serve this savory tart with a green salad for the perfect brunch, lunch or light dinner.
If you don’t have buttermilk on hand, or you’re lactose-intolerant, use soured milk instead. Add one tablespoon (15 ml) white vinegar to the bottom of the measuring cup and fill to the top with regular or lactose-free milk. Stir and continue with the recipe.
Chicken, Tomato and Gruyère Tart
Serves 4 to 6, Adapted from Fine Cooking
3 ounces (56 grams) or 1 cup (240 ml) coarsely grated Gruyère cheese
1/3 cup (80 ml) mayonnaise
1/4 cup (60 ml) finely chopped chives
2 tablespoons (30 ml) finely minced fresh basil
1/2 teaspoon (2.5 ml) dried oregano
1/8 teaspoon (.62 ml) pepper
2 cooked chicken breasts (about 12 ounces or 340 grams), thinly sliced
8 ounces (230 grams) sliced, ripe tomatoes, seeds removed
148 grams (1 cup or 240 ml) superfine brown or white rice flour
57 grams (1/3 cup or 80 ml) potato starch
35 grams (1/4 cup or 60 ml) tapioca flour
2 teaspoons (10 ml) baking powder
1/2 teaspoon (2.5 ml) baking soda
1/2 teaspoon (2.5 ml) salt
6 tablespoons (168 grams/90 ml) cold, unsalted butter, cut into small pieces
3/4 cup (180 ml) buttermilk or soured milk (regular or lactose-free), see above
4 tablespoons (60 ml) potato starch, divided in half
Mix the cheese, mayonnaise, chives, basil, oregano and pepper in a small bowl. Set aside. Fold a clean dish towel in half and spread the tomato slices over it in a single layer so that the juices will be absorbed while you make the crust. Slice the chicken breasts and set aside.
Place a rack in the center of the oven and heat the oven to 450º F (230º C). In a large bowl, add the rice flour, potato starch, tapioca flour, baking powder, baking soda, and salt, then whisk together. Add the butter and use a pastry blender or fork to cut the butter into the flour until it looks like cornmeal with a few larger bits of butter scattered through-out. Add the buttermilk. Mix until the flour is moistened, then use your hands to knead the dough 10 to 12 times.
Place a 12 x 17 inch (30 x 42 cm) piece of parchment paper or foil on the table and scatter 2 tablespoons (30 ml) of potato starch on top. Scrape the dough onto the parchment and knead until a pliable dough forms, sprinkling with potato starch to keep it from sticking. Lift the dough and dust the foil with more potato starch, then gently pat the dough into a 5 inch (12.5 cm) circle. Dust the top with potato starch and use a rolling-pin to roll the dough into a 13 inch (32 cm) circle. If the dough cracks, fold it up and knead it a few more times before rolling it out again. You should see streaks of butter and the surface should be smooth. Unlike wheat pastry, you can’t over knead gluten-free dough.
Dust the center of the dough with 2 tablespoons (30 ml) of potato starch, leaving a 1 1/2 ” (3.75 cm) border. Spread the chicken slices in a single layer across the center of the dough, followed by the tomatoes. Drop small dollops of the cheese and herb mixture over the tomatoes. Carefully fold the dough border over the outside edge of the filling, pleating the dough as needed to keep the tart round. Don’t worry if the dough breaks; if it does, gently pat the pieces together. The edge of the dough will look ragged, but this adds to the rustic look, so don’t worry about it. The tart will be about 10 inches (25 cm) across.
Holding the edge of the parchment paper, slide the tart onto a large rimless baking sheet and put it on the center rack of the oven.
Bake until golden-brown, about 20 to 25 minutes. Using the edge of the parchment paper, slide the tart onto a wire rack, slipping the paper out from underneath so that the bottom stays crisp as it cools. Let it cool for 30 minutes before serving.