The streusel on the crumb cake is left intentionally clumpy and dominating, providing a noticeable contrast in texture to the tender and moist cake below. Finally, on top, you can dust the crumb cake with confectioners’ sugar, adding an appealing snow-white layer to the brown streusel.
Another difference between the two cakes (and this is less subtle) is that while it’s common to add streusel to coffee cake, it doesn’t always require it. You could always substitute the crumb topping with other toppings like icing, nuts, fruits and berries, and confectioners’ sugar to make different varieties of coffee cake; however, you simply can’t skip the streusel layer when it comes to the crumb cake.
Despite these subtle and not-so-subtle differences, coffee and crumb cakes are delightful companions to your tea or coffee. So, whether you’re a streusel lover or prefer tender cakes with just a touch of crumb, there’s a treat out there waiting to tickle your tastebuds.