In a large mixing bowl, combine the fresh cranberries, granulated sugar, orange zest, orange juice, cornstarch, and ground cinnamon. Toss the ingredients together until the cranberries are evenly coated with the mixture.

Transfer to Baking Dish

Pour the cranberry filling into a greased 9x13 inch baking dish, spreading it out evenly.

Topping Preparation

Mix Dry Ingredients

In a separate mixing bowl, whisk together the all-purpose flour, granulated sugar, baking powder, and salt until well combined.

Incorporate Butter

Cut the unsalted butter into small pieces and add it to the dry ingredients. Use a pastry cutter or your fingers to mix until the mixture resembles coarse crumbs.

Add Milk

Gradually pour in the milk, stirring with a spatula until just combined. Do not overmix; the batter should be slightly lumpy.

Combine and Bake

Spread Topping Over Filling

Spoon the batter over the cranberry filling in the baking dish. Use a spatula to spread it out evenly, allowing some of the filling to peek through.

Bake the Cobbler

Preheat your oven to 375°F (190°C). Bake the cobbler for 35-40 minutes, or until the topping is golden brown and a toothpick inserted into the topping comes out clean.

Cool and Serve

Remove the cobbler from the oven and let it cool for at least 10 minutes before serving. Serve warm with vanilla ice cream or whipped cream, if desired.