Preheat oven to 325 degrees F. Line a 9 x 13 casserole dish with parchment paper across the center with overhangs to easily remove cake later. Lightly spray casserole dish with cooking spray both under and over parchment paper; set aside.
2. To make the cake - In a bowl fit with a mixer, combine flour, granulated sugar, ground cinnamon, baking powder, baking soda, and salt. Whisk to combine mixture. Slowly beat in chunks of shortening and butter. Once mixture starts to blend more, turn up mixer and carefully beat until mixture is semi-crumbly; set aside.
3. In a medium bowl, whisk together sour cream, milk, egg whites, Mexican vanilla, butter extract, and almond extract.
4. Slowly pour wet mixture into dry ingredients while beating on slow. Once mixture is semi-blended, turn up mixer and carefully beat just until combined; about 1-2 minutes. Careful not to over mix batter.
5. Pour mixture into prepared casserole dish. Bake for 65 minutes or until center is set and a toothpick inserted in the center comes out clean.
6. Allow cake to cool then removed it from the dish. Run a knife flat along the top of cake to create a flat cake. Remove extra cake from surface as this surface should be level.
7. Next, cut all edges of cake to be flat as well. At this point, the cake should be perfectly level and rectangular.
8. Next, cut the cake in half horizontally. To do this, decide where the center of the cake is. Run a knife through it with a piece of parchment behind it as to carefully pick the top layer off without the cake cracking.
9. Cover cakes with plastic wrap; set aside.
10. To make the frosting - In a bowl fit with a mixer, beat butter, powdered confectioner's sugar, and cinnamon; about 3 minutes or until smooth.
11. Beat in salt, Mexican vanilla extract, and butter extract.
12. Turn up mixer and beat in chunks of cream cheese and shortening. Mix frosting until smooth.
13. Frost bottom cake top as this will serve as the filling. Place top cake on and frost with remaining frosting. I used a cake spatula to evenly spread frosting around.
14. Chill cake overnight or at least a few hours. Only make churros right before serving cake as they will become stale and soft if covered or refrigerated.
15. To make the churros - Heat 2 quarts vegetable oil in stockpot. Heat oil to 350 degrees F. I used a meat thermometer to check for the correct temperature.
16. In a medium saucepan boil water, sugar, oil, and salt. Spoon wet mixture into a medium bowl with flour using a measuring cup. Mix until blended and dough has formed. Fill piping bag with dough and cut tip off the end; about the size of your pinky.
17. Pipe dough into hot oil and fry until golden brown. Toss with cinnamon sugar.
18. Cut churros into pieces that will fit onto the top of the cake.
Slice cake and serve.