• Preheat oven to 375 F. Grease a 9 x 13 inch pan.

For the fruit filling:

• Trim fresh rhubarb and remove any rough sections. Cut raw rhubarb into 1 inch pieces. If using strawberries, hull and slice straberries into quarters and combine with cut rhubarb pieces.
• In a large bowl, combine rhubarb, strawberries (if using), sugar, orange or lemon juice and zest, and ginger. Spread fruit mixture in prepared baking dish.
• For the crunchy topping:
• In a medium bowl, whisk together brown sugar, flour, cinnamon, rolled oats, and nuts.
• Cut cold butter into 1/2-inch cubes. Use your finger tips to rub the butter into the flour mixture until no more chunks of butter remain, and the mixture begins to clump together. Sprinkle the crumbly topping over the prepared rhubarb mixture.
• Place in preheated oven. Bake 45 to 50 minutes until the topping is golden brown and the fruit is juicy. If the topping begins to brown too much and the fruit is not yet stewy and juicy, cover lightly with aluminum foil and continue baking.

For the sour cream whipped cream:

• In the bowl of a stand mixer using the whisk attachment, whip the whipping cream on low speed until it thickens. Increase speed and beat until soft peaks form. Add in sour cream and whisk to combine.
• Serve warm topped with sour cream whipped cream and/or a scoop of vanilla ice cream. This easy rhubarb crisp, served a la mode, just may be our favorite dessert ever.