Instructions

1. Preheat the oven to 350°F (175°C).
2. In a bowl, mix together the flour, oats, sugars, and salt. Pour in the melted butter and stir with a fork until coarse crumbs form. Place the crumble topping in the refrigerator while you prepare the filling.
3. Cut the strawberries into evenly sized pieces, about 1/2 to 3/4 inch, then toss them in a large bowl with sugar, cornstarch, lemon juice, and vanilla until evenly coated.
4. Lightly grease a baking dish or cast-iron skillet that holds about 2 to 2.5 quarts. Spread the strawberry mixture evenly on the bottom, then sprinkle the crumble topping over the fruit, making sure it reaches all the edges.
5. Place the dish on a baking sheet (to catch any bubbling juices) and bake for about 40–45 minutes, until the topping is golden and the filling is bubbling around the edges.
6. Let it cool slightly before serving so the filling can set. Serve warm, plain, or with a scoop of vanilla ice cream.