Chuck's Mixed Tomato Cobbler With Gruyere Crust: Pushing Daisies

Why I Love This Recipe
One of the best from The Pie Hole
Ingredients You'll Need
1 1/2 cup all-purpose flour plus
2 tbl all-purpose flour
1 1/2 tsp coarse salt
2 tsp sugar
3/4 cup Gruyere cheese
1/2 cup cold unsalted butter plus
1 tbl cold unsalted butter cut in pieces
1 lrg yellow onion diced
3 x garlic cloves finely minced
2 lb assorted cherry tomatoes
1/4 cup chopped fresh basil
1 pch freshly-ground black pepper
1 lrg egg
Directions
the bowl of a food processor, combine 1 1/4 cups flour, 1/2 teaspoon salt, 1/2 teaspoon sugar, and 1/2 cup Gruyere cheese. Add 1/2 cup butter; process until mixture resembles coarse meal, 8 to 10 seconds.
* With machine running, pour about 1/8 cup ice water, little by little, through feed tube. Pulse until dough holds together without becoming wet or sticky; be careful not to process more than 30 seconds. To test, squeeze a small amount together; if it is crumbly, add more water, 1 teaspoon at a time.
* Flatten dough into a disk; wrap in plastic. Transfer to refrigerator; chill 1 hour.
* Melt remaining tablespoon butter in a large skillet over medium heat. Add onion and garlic. Cook, stirring occasionally, until translucent and softened, 5 to 7 minutes. Transfer to a bowl, and cool slightly.
* Place tomatoes in a large bowl. Toss with remaining 1/4 cup plus 2 tablespoons flour, 1 teaspoon salt, 1 1/2 teaspoons sugar, and the basil and pepper. Add onion mixture, and toss to combine. Transfer mixture to a deep 9-inch pie dish. Set aside.
* Heat oven to 375 degrees. Roll out dough into a circle 1 inch larger than pie dish. Transfer rolled dough to top of dish; tuck in edges to seal, forming a decorative edge, if desired. Cut four 1-inch slits in crust.
* In a small bowl, mix egg with 1 teaspoon water. Brush egg glaze over crust; sprinkle crust with remaining 1/4 cup cheese. Place pie dish on a baking sheet lined with a Silpat to catch drips. Bake until crust is golden and inside is bubbling, about 50 minutes. Let cobbler cool before serving.
* This recipe yields 8 servings.
* Comments: This recipe, which originally appeared in Martha Stewart Living magazine, has become one of Oprah Winfrey's favorites. Martha recommends keeping the dough cold until it's time for baking and also suggests letting the cobbler cool for a few minutes before serving, to allow the tomato juices to collect