Upside Down Tomato Tart

2 tablespoons bacon drippings 4 cups heirloom cherry tomatoes 1/2 large sweet onion, sliced into think half moons 1/2 teaspoon lemon pepper seasoning 1/4 teaspoon red pepper flakes Salt and pepper Cooking spray Juice of 1/2 lemon 1/2 cup grated asiago cheese 1 9 inch square piece frozen puff pastry ( half of a 17 ounce package), thawed Chopped fresh basil for topping 

1. Preheat oven to 400 degrees. Line baking sheet with parchment paper. Microwave the bacon drippings for 8 to 10 seconds to melt, if necessary. Combine the tomatoes, onion, bacon drippings, lemon pepper, red pepper flakes, 1/2 teaspoon salt and 1/4 teaspoon pepper in a large bowl. Spread the prepared baking sheet and roast until slightly softened about 10 minutes. Let cool. Reduce the oven to 375

2. Coat the bottom and side of an 8- or 9- inch cast iron skillet with cooking spray. Toss the tomato mixture with the lemon juice and Asiago; spread evenly in the skillet. Place the puff pastry on top; trip the over hanging pastry. 
3. Transfer the skillet to the oven and bake until the pastry is dark golden, about 50 minutes. Let cool about 5 minutes then place a large plate or platter on top of the skillet and invert the tart. Sprinkle with basil and let cool 5 more minutes.