Ingredients
Cornmeal Galette Dough
1-1/4 cups (5 oz.) all-purpose flour
1/3 cup (1–1/2 oz.) fine yellow cornmeal
1 tsp. sugar
1–1/4 tsp. salt
6 T. (3 oz.) unsalted butter, cut into 1/2-inch pieces and well chilled ,
3 T. olive oil
1/4 cup ice water
Finishing the tart:
2 Tbs. olive oil
1 medium sweet white onion, thinly sliced
Salt and freshly ground black pepper
2 cloves garlic, chopped finely
1/2 bunch basil, washed, dried, and coarsely chopped, (to yield about 1/2 cup); plus 10 whole leaves
Kernels from 1 ear of Lepp’s sweet corn (about 1 cup)
1 large or 2 medium ripe roma tomatoes (about 3/4 lb. total) cut into 1/3-inch slices, drained on paper towels
4 oz. Gruyère cheese, shredded
1 large egg yolk mixed with 1 tsp. milk or cream
Instructions
Cornmeal Galette Dough
In a medium bowl, mix together the flour, cornmeal, sugar, and salt.
Cut in the chilled butter using a stand mixer, a food processor, or a pastry blender until it’s evenly distributed but still in large, visible pieces, even as large as a sugar cube.
Add the olive oil and ice water and mix until the dough begins to come together.
Gather the dough with your hands and shape it into a disk. Wrap the disk in plastic and refrigerate for at least 1 hour.
Finishing the tart:
Heat the olive oil in a sauté pan, preferably nonstick, over medium heat. Add the sliced onion and cook, stirring frequently, until lightly browned, about 10 minutes. Season with salt and pepper. Add the garlic, chopped basil, and corn and cook for 30 seconds. Transfer the mixture to a bowl and set aside to cool.
Adjust an oven rack to the center position and heat the oven to 375°F. Line a baking sheet, preferably one without sides, with parchment paper. (If your baking sheet has sides, flip it over and use the back.)
Roll the dough on a floured surface into a 15-inch round, lifting the dough with a metal spatula as you roll to make sure it’s not sticking. If it is, dust the surface with more flour. Transfer it by rolling it around the rolling pin and unrolling it on the lined baking sheet. It’s important to move the dough round to the parchment paper lined baking sheet before assembling it, as you’ll never be able to move it once you’ve added the filling.
Spread the onion and corn mixture over the dough, leaving a 2-inch border without filling. Sprinkle the cheese over the onions and corn. Arrange the tomatoes in a single layer over the cheese and season them with salt and pepper. Lift the edges of the dough and fold them inward over the filling, pleating as you go, to form a folded-over border. Pinch together any tears in the dough. Brush the egg yolk and milk mixture over the exposed crust.
Bake until the crust has browned and the cheese has melted, 35 to 45 minutes. Slide the galette off the parchment and onto a cooling rack. Let cool for 10 min. Stack the remaining 10 basil leaves and use a sharp knife to cut them into a chiffonade. Cut the galette into wedges, sprinkle with the basil, and serve.
