Preheat the oven to 190°C (375°F) and grease a 2-quart baking dish.

In a large bowl, toss the strawberries with granulated sugar, cornstarch, lemon juice, and vanilla extract until evenly coated.

In a separate bowl, combine the flour, oats, brown sugar, cinnamon, and salt.

Using a pastry cutter or fingers, work the cold butter into the dry mixture until it resembles coarse crumbs with pea-sized pieces.

Spread the strawberry mixture evenly into the prepared baking dish.

Distribute the crumble topping uniformly over the fruit layer.

Bake for 35 to 40 minutes until the fruit juices are bubbling and the topping is golden brown.

Allow to cool for at least 15 minutes before serving to let the juices set.