Preheat oven to 375°F (190°C). Grease a 9x13 inch baking dish.
In a large bowl, combine the sliced peaches, 0.75 cup granulated sugar, 2 tablespoons flour, cinnamon, nutmeg, and lemon juice. Toss gently to coat. Pour the peach mixture into the prepared baking dish.
In a separate medium bowl, whisk together 1.5 cups flour, 0.5 cup granulated sugar, baking powder, and salt.
Cut in the cold butter using a pastry blender or your fingertips until the mixture resembles coarse crumbs.
Stir in the milk until just combined. Do not overmix.
Drop spoonfuls of the biscuit topping evenly over the peach mixture. It doesn't need to cover completely.
Bake for 35-45 minutes, or until the topping is golden brown and the peach filling is bubbly.
Let cool for at least 10 minutes before serving. Serve warm, perhaps with a scoop of vanilla ice cream.
Notes
Adjust sugar based on the sweetness of your peaches. For a richer flavor, you can add a tablespoon of vanilla extract to the peach filling.