Preheat oven to 350 degrees.

Rinse, core and quarter fresh strawberries into a large mixing bowl. To the strawberries, add your cornstarch, sugar, lemon zest, and lemon juice. Stir to coat all the berries.

Transer berry mixture to a buttered, 2-quart baking dish or a 9-10" pie plate.

In a medium bowl, combine flour, oats, brown sugar, nuts (if including), salt and cinnamon. Add in melted butter and stirn until mixed and crumbly.

Sprinkly topping over strawberry mixture.

Bake for 45-50 minutes, or until berries are bubbling and the topping is a nice golden brown.

Let cool 10-15 minutes before serving.