Heirloom Tomato Galette with Caramelized Onions & Ricotta
The recipe starts with basic pie dough for the crust, which is rolled out and filled with creamy ricotta cheese, caramelized onions, sweet and juicy heirloom tomatoes and Parmesan cheese creating an appetizer that eases out of summer and into fall.
To make the dough, place the flour, sugar and salt into a food processor. Pulse for a few seconds to combine. Pour 6 tablespoons of cold water over a few ice cubes. Let sit for a few seconds to chill. Remove the ice cubes from the chilled water, and add the butter and 6 tablespoons of the water to the flour mixture.
Pulse until the mixture forms a rough dough. Turn out onto a lightly floured surface and knead the dough. Form into a square, wrap in plastic wrap and refrigerate for at least 10 minutes.
For the caramelized onions:
Heat a large sauté pan over medium heat, add the olive oil and heat through. Add the butter and allow to melt. Add the onions and toss quickly to remove the moisture from the onions. Sauté, stirring occasionally, until the onions are soft and start to brown.
Sprinkle the salt and sugar over the onions (to help them caramelize) and reduce the heat to medium-low and cook, stirring occasionally, until the onions are light brown and begin to caramelize, about 20 minutes.
Add the balsamic and stir to combine. Continue to cook until the onions are uniformly brown and caramelized, about an additional 10 minutes. Remove from the pan and set aside.
For the filling:
Heat oven to 375ºF (190ºC).
Roll the dough out into an 16-inch by 12-inch rectangle. Transfer the dough to a parchment paper lined baking sheet or quarter sheet pan. Spread the ricotta over the dough leaving a 2-inch border around the edges.
Arrange the caramelized onions over the ricotta then layer the heirloom tomatoes over the top. Sprinkle with Parmesan cheese then fold the outer edge of the dough over itself to form a crust over the tomatoes. Brush the edges with the beaten egg.
Bake until the edges are golden brown, about 50 minutes. Let cool completely and sprinkle with flaky sea salt.