Preheat oven to 350°F. Grease or butter the inside of a 13 x 9-inch cake pan or two 8-inch pans.
Combine the flour, chai spices, baking powder, baking soda, and salt in a small bowl and set aside.
Cream the butter and sugar together in an electric mixer.
Add the eggs one at a time. Slowly add the milk and pumpkin puree.
Gradually add the flour mixture a little at a time until everything is well blended.
Spread the batter evenly into the prepared cake pan.
In the same bowl used for the flour mixture, mash together the flour, brown sugar, butter, and chai spices for the topping with a fork until moist crumbles form.
Sprinkle the crumbs evenly over the cake batter.
Bake for approximately 35-40 minutes, or until a toothpick inserted into the center comes out clean.
Let cool before serving.