Tomato, Caramelized Onion, and Goat Cheese Crostata

Heat a large skillet over medium-low heat. Add the olive oil, onions, and a good pinch of salt. Cook slowly for about 20-30 minutes, stirring occasionally until the onions are soft and deep golden brown. Set aside (this can be done up to 5 days before). Preheat the oven to 425 degrees Fahrenheit. Unroll the pie crust on a parchment-lined sheet pan. In a bowl, whisk or beat 1 egg, goat cheese, heavy cream, the Parmigiano-Reggiano, and 1/2 teaspoon of salt. Add the sliced basil and stir. Spread the cheese filling onto the pie crust, leaving a 1-inch border around the edges. Add the caramelized onions on top of the cheese. Arrange cherry tomatoes on top of the cheese and onions. Fold dough edges over the filling to form a border, pleating the dough as you go. Brush the dough with an egg wash using the remaining egg. Bake on the middle rack for approximately 18-25 minutes, or until golden brown. Let cool. Garnish with additional basil if desired.