Preheat oven to 425°F (220°C).

In a large saucepan, combine sliced peaches, 1 cup granulated sugar, brown sugar, cinnamon, nutmeg, lemon juice, and cornstarch.

Cook over medium heat until the mixture begins to bubble and thicken slightly, about 10 minutes. Remove from heat.

Pour the hot peach mixture into a 2-quart baking dish.

In a mixing bowl, whisk together flour, 1 cup granulated sugar, baking powder, and salt.

Cut in the butter with a pastry cutter or fork until the mixture resembles coarse crumbs.

Stir in boiling water just until combined to form a lumpy batter.

Drop spoonfuls of the batter over the hot peach filling.

Bake in the preheated oven for 25-30 minutes, or until the topping is golden brown and the peach filling is bubbling.

Allow to cool slightly before serving. Best enjoyed warm with vanilla ice cream.