Preheat the oven to 350 degrees F. In a medium bowl, mix the rhubarb and the strawberries with the sugar, corn starch, and orange zest. Let sit for 30 minutes to bring out the juices.

In a separate medium bowl, whisk together 2 tablespoons of sugar, flour, baking powder, cinnamon, and salt. Cut the butter in with a pastry blender or your hands. Combine until the mixture resembles coarse crumbs. Add in the milk, egg, and vanilla, stir until just moistened. Don't overmix.

Pour strawberries and rhubarb into a 2-quart casserole dish or individual casserole dishes/ramekins.  Drop the cobbler batter on top of the fruit. Sprinkle turbinado sugar over the cobbler topping. Bake for 30-35 minutes until cobbler crust is golden brown and fruit filling is bubbling. If desired, serve with whipped cream or vanilla ice cream.