TOMATO-AND-CHEESE COBBLER

Steps:

• Preheat oven to 400°F. Gently toss tomato slices with 1 Tbsp. salt in a medium bowl, then arrange in an even layer on paper towels. Let sit until most of the juices are released, about 15 minutes. Pat tomatoes dry with more paper towels.
• Meanwhile, whisk pepper, baking powder, baking soda, 1 1/2 cups flour, and 1/2 tsp. salt in a large bowl to combine. Cut in butter with a pastry cutter or 2 butter knives until pea-size pieces form. Stir in buttermilk, chives, and 3/4 cup cheese with a wooden spoon until a shaggy dough forms.
• Turn out dough onto a lightly floured work surface. Gently knead 2-3 times until dough just comes together, being careful not to overwork. Roll out dough to 3/4" thick. Cut with a 2" flour-dipped biscuit cutter or small glass. Transfer to a plate or baking sheet and chill until ready to use.
• Pour oil into a large deep heatproof skillet or braising dish. Arrange tomato slices in even layers in pan (you'll have about 3 layers); top with thyme. Roast until tomato juices start to bubble, 15-20 minutes.
• Discard thyme sprigs. Flatten tomatoes into an even layer with a spatula, then sprinkle with remaining 3/4 cup cheese. Arrange biscuits over, spacing about 1" apart. Whisk egg and 1 Tbsp. water in a small bowl. Brush biscuits with egg wash. Bake until biscuits are golden brown and firm to the touch, 18-20 minutes. Let cool 5-10 minutes before serving.
• Do Ahead: Dough can be formed into biscuits 8 hours ahead. Keep chilled.