Preheat your oven to 375°F.
Prepare your peaches. If using fresh peaches, peel and slice them. If using frozen, thaw and drain. If using canned, drain well. Toss peaches with half the sugar and cinnamon.
Melt the butter and pour it into the bottom of your baking dish.
In a bowl, whisk together flour, remaining sugar, baking powder, salt, milk, and vanilla until smooth.
Pour the batter over the melted butter—do not stir.
Spoon the peaches and juice evenly over the batter. Again, don’t stir. The magic of cobbler is letting the batter rise around the peaches as it bakes.
Bake for 40–45 minutes, or until golden brown and bubbling.
Serve warm with vanilla ice cream or whipped cream.