Preheat the oven 350 degrees F (180 degrees C). In the first bowl, whisk together Canola Oil (1/4 cup), Granulated Sugar (1/2 cup), Vanilla Extract (1 teaspoon), Milk (3/4 cup) and Egg (1). Whisk until foamy.
In the second bowl, sift together the Unbleached All-Purpose Flour (1 1/2 cup), Baking Powder (2 teaspoon) and Fine Sea Salt (1/2 teaspoon).
Slowly combine the 2 bowls by adding the dry ingredients in thirds into the bowl with the wet ingredients. Do not over mix.
In a greased cake pan, spoon in half the batter.
To make the filling, combine Ground Cinnamon (1 1/2 teaspoon) and Brown Sugar (1/2 cup) in a bowl and mix well. Sprinkle the batter in the pan with the brown sugar and cinnamon mixture and spread the rest of the batter evenly on top.
To make the crumble, combine Unbleached All-Purpose Flour (1/3 cup), Granulated Sugar (1/2 cup), Fine Sea Salt (1/4 teaspoon), Unsalted Butter (1/4 cup) and Ground Cinnamon (3/4 teaspoon) Dot the crumble generously on top of the cake.
Bake at 350 degrees F (180 degrees C) for 17-21 minutes.
Cool and allow to set before slicing and serving.