A creamy mushroom topping fills this deep, crusty pizza. Martha made this recipe on Martha Bakes episode 608.
Preheat oven to 500 degrees with rack in lowest position. Melt butter in a large skillet over medium-high heat. Add shallots; cook until softened, about 2 minutes. Add mushrooms, 1 1/2 teaspoons salt, and 1/4 teaspoon pepper; cook until mushrooms are golden brown, 5 to 7 minutes. Add wine, bring to a boil, and cook until absorbed, about 1 minute. Add cream and stir to combine. Transfer to a plate, and let cool.
Working with one piece of dough at a time, gently stretch into a 9-inch circle and place in an 8-inch cast-iron skillet. Brush dough all over with olive oil, and sprinkle with 1-ounce cheese, and one-quarter of the mushrooms. Top with another ounce of cheese. Drizzle with oil, and season with salt and pepper.
Place skillet in the oven and bake until crust is golden brown, 15 to 16 minutes. Sprinkle with tarragon and cut into wedges. Serve immediately. Repeat process with remaining ingredients.