Preheat your oven to 350°F and toss a few slices of butter into a 9x13 baking dish. Let it hang out in the oven while it heats up—your dish gets warm and the butter gets melty.
Meanwhile, mix the blueberries, sugar, and lemon zest in a bowl.
In another bowl, whisk together the flour, sugars, baking powder, cinnamon, and salt. Add the milk and stir just until it comes together; don’t overmix it.
Once the butter’s melted, pull the dish from the oven. Scatter the blueberries right over the butter (don’t stir!), then pour the batter over the top. Finish with a sprinkle of cinnamon for that cozy cobbler magic.
Bake for 45-55 minutes (honestly, mine needs closer to 55, but check on it starting at 45), or until the top is golden and the edges are bubbly. Serve warm with ice cream if you know what’s good. 💙🍦