Prepare a 9x13-inch baking pan and preheat oven to 350°F.
For the cake, put flour, sugar, salt, baking powder and vanilla into a mixing bowl. Mix using the beater attachment on low speed.
Add vegetable oil and milk, and continue mixing on low speed. Mix until smooth.
Add the eggs gradually on low speed and let them mix in. Scrape down the bowl and then let mix. Cake batter should be smooth with no lumps.
For the crumbs, put both sugars, cinnamon, and salt in a mixing bowl using the beater attachment and mix on low speed until ingredients are just combined. Add vegetable shortening and mix until smooth.