In a large bowl combine fruit, sugar, basil,cinnamon and cornstarch.
Pour into prepared pan in an even layer.
In the same bowl combine the flour, oats, sugar and salt. With the back of a wooden spoon or spatula ensure the dry ingredients are well mixed and there are no lumps of brown sugar.
Add in the butter and with a fork mix until crumbly.
Spread in an even layer on the fruit.
Bake 45-50 minutes until bubbling and golden brown on the top.
Serve warm.
Recipe by Chateau Elma at https://www.chateauelma.com/rhubarb-strawberry-crisp