Warm berry cobbler with a golden, buttery topping over juicy mixed berries is a comforting family dessert. This rustic, easy-to-make treat is best served warm with vanilla ice cream.
Preheat the oven to 375°F (190°C) and butter an 8-inch square baking dish or similar casserole dish.
Scatter the mixed berries evenly over the bottom of the prepared dish. If your berries are very tart, sprinkle 2 tbsp of sugar from the measured amount over them.
In a bowl, whisk together flour, remaining sugar, baking powder, and salt until well combined.
Melt the butter and let it cool slightly. In another bowl, whisk together melted butter, milk, and vanilla extract.
Add wet ingredients to dry ingredients and stir just until a thick, slightly lumpy batter forms. Do not overmix to keep the topping tender.
Drop spoonfuls of the batter evenly over the berries, covering most of the fruit but leaving some gaps for juices to bubble through. Sprinkle lemon zest on top if using.
Bake for 38–42 minutes on the center rack, until the topping is golden brown and a toothpick inserted into the topping comes out clean.
Let the cobbler rest for 10 minutes before serving. Serve warm, ideally with a scoop of vanilla ice cream.