Gather your ingredients and preheat the oven to 375°F (190°C). In a large mixing bowl, toss 500 g blueberries (wash if fresh first), with 25 g sugar and 12 g cornstarch. Zest and squeeze the juice of 1 lemon.
In another mixing bowl, using a spatula, combine the 200 g brown sugar, 150 g rolled oats, 120 g unsalted butter, 60 g all-purpose flour, 1/2 tsp. salt and 1/2 tsp. ground cinnamon until crumbled.
The Baking
Butter a baking pan or dish. I use a round baking pan with some parchment paper.
First spread half of the topping mixture.
Then spread the blueberries mix.
Sprinkle the second half of the topping mixture evenly over the blueberries in the baking dish.
Bake 35-40 minutes at 375°F or until the fruit filling is hot and bubbly and the topping is golden brown.
Let the crisp cool on a wire rack for at least 60 minutes before serving.
The Serving
Serve warm. Enjoy the Blueberry Crisp [Croustade aux bleuets].