This coffee cake is a delicious way to start your day. The cake is made with a tender and moist crumb, topped with a layer of sweet and tangy strawberry rhubarb filling, and finished with a crunchy streusel topping. To make the cake, cream together butter and sugar, then add eggs and vanilla. In a separate bowl, mix together flour, baking powder, and salt. Add the dry ingredients to the wet mixture, alternating with milk. Pour the batter into a greased baking dish, then top with the strawberry rhubarb filling and streusel topping. Bake until golden brown and serve warm with a cup of coffee or tea.