Five-Spice Sweet Potato Crumb Cake

For my mom

The birthday gifts I tend to give usually revolve around a meal or baked good I make specifically for that person. Over the holiday I polled my family members on their favorite sweets, just to make sure I had their tastes right (my dad = warm fruit crisp with vanilla ice cream, my brother = a big, soft oatmeal chocolate chip cookie, Anthony = super-tart…