Preheat the oven to 350°F.
In a medium bowl, stir together the blueberries, maple syrup, lemon juice, vanilla extract, and coriander. Pour the mixture into the bottom of an 8x8-inch baking dish and set aside.
4 cups (665 g) fresh or frozen blueberries, 2 tbsps. (30 ml) maple syrup, 1 tbsp. (15 ml) fresh lemon juice, 1 tsp. (5 ml) vanilla extract, 1/4 tsp. ground coriander
In a large bowl, add the softened butter, granulated sugar, and sea salt. Use a mixer to beat until light and fluffy. Beat in the egg until well combined.
6 tbsps. (90 g) unsalted butter, 1/2 cup (117 g) granulated sugar, 1/4 tsp. fine sea salt, 1 large egg
Add the flour, baking powder, and cinnamon, and mix until just combined. Stir in the milk with a wooden spoon until the batter is smooth.
1 cup (130 g) all-purpose flour, 1 tsp. baking powder, 1 tsp. ground cinnamon, 1/2 cup (125 ml) whole milk
Drop spoonfuls of the batter over the blueberry mixture, spreading it out to cover most (but not all) of the berries.
Bake for 45–60 minutes, or until the top is golden brown and the berries are bubbling. (Baking time will be longer if using frozen berries.)
Serve warm with a scoop of vanilla ice cream or a dollop of whipped cream, if desired.
ice cream or whipped cream for topping, optional