Preheat your oven to 350 degrees F. Spray three 8-inch or four 6-inch pans with non-stick spray, line the bottoms of each pan with parchment rounds, and spray again. Set aside.
In a large liquid measuring bowl, combine the almond milk, vanilla, oil and vinegar. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, combine the cake flour, sugar, baking soda, and salt. Stir to combine.
With the mixer on low speed, add the wet ingredients to the dry ingredients. Stir just until incorporated. Scrape down the sides and bottom of the bowl and mix again on low for another 10 to 20 seconds.
Divide the batter evenly between the three pans (about 16 ounces of batter in each pan). Bake for 22 to 25 minutes, or until a toothpick inserted in the center of the cake comes out with just a few moist crumbs on it.
Let cool 10 minutes in the pans before inverting onto wire racks to cool completely.
If needed, level each cake layer with a cake leveler. To store the cake layers, wrap each cake layer in plastic wrap after it's completely cooled. The cake layers can be stored in the freezer for up to a week with two layers of plastic wrap. To store longer, wrap the layers in an additional layer of foil and place in a zip-lock bag.
FOR THE FROSTING
In the bowl of a stand mixer fitted with the paddle attachment, combine the vegan butter and shortening. Beat on medium speed until light and fluffy, about 2 minutes.
With the mixer on low speed, gradually add the sifted powdered sugar and then vanilla. Once the sugar and vanilla are incorporated, turn the mixer to medium-high and beat for an additional 3 to 5 minutes.
To get rid of any air pockets, use a wooden spoon or spatula to stir the frosting by hand for a couple minutes.
ASSEMBLY
Place the first cake layer bottom-side down, in the center of the cake board. Using an offset palette knife, spread about 3/4 cup frosting evenly across the cake layer. Layer with strawberries, if using.
Place the second cake layer on top of the frosting. Frost the top of the second cake and add strawberries, if using.
Place the third cake layer, top side down, on top of the frosting.
Crumb coat the entire cake with a thin layer of frosting and freeze for about 10 to 15 minutes to set.
Once the crumb coat is set, continue to frost the cake with the remaining frosting.
Notes
*Hi-ratio shortening contains more emulsifiers than regular shortening, giving it a smoother and creamier texture than regular shortening. Hi-ratio shortening is also more stable than regular shortening.