Preheat the oven to 180C. rinse the blueberries (no need to thaw if using frozen) , then dump them directly into your baking dish.
Mix the blueberries with the maple syrup/honey, cornstarch, lemon zest, lemon juice and cinnamon. Toss until combined.
In a separate mixing bowl, stir together oats, almond meal, sliced almonds, brown sugar and salt.
Mix in the melted butter and the yogurt and stir until mixture is combined and moistened throughout.
Using your fingers, crumble spoonfuls of the oat mixture over the filling until evenly distributed.
Bake 40-50 minutes until filling is bubbling and top is golden. Rest for 5-10 minutes before serving. Don't forget the vanilla ice cream!