Preheat oven to 350F. Grease a pan. Wash and slice the strawberries and rhubarb.
1) Make fruit sauce: Combine all ingredients into a medium sauce pan.
Cook them over medium heat, until rhubarb is soft and liquid has thickened, about 20 minutes.
2) Make crumb topping: Combine all ingredients in a medium bowl. Using a fork or your fingers, mix them until crumbly.
Put the crumb in a fridge until use.
3) Make cake butter: Combine first 5 ingredients in a large bowl.
Using a pastry knife or forks, cut the butter into flower mixture until it resembles coarse meal.
In a small bowl, mix the eggs, milk and vanilla. Pour into flour mixture and stir to combine.
Spread half the cake batter evenly into the prepared pan. Top with half the fruit sauce.
Carefully spread the remaining cake batter over the fruit, and top with the remaining fruit sauce.
Sprinkle with the crumb topping. Bake about 1 hour or until cake is golden brown.
Let the cake cool slightly on a wire rack. Cut into squares, serve warm or at room temperature.