Preheat the oven to 350°F (175°C). Lightly grease two 9-inch round cake pans with nonstick baking spray and line the bottoms with parchment; set aside.
In a medium bowl, whisk together the all-purpose flour, cocoa powder, baking soda, and fine salt until evenly combined, about 30 seconds.
In a large bowl, whisk the granulated sugar and vegetable oil until glossy and emulsified, about 1 minute.
Whisk in the large eggs one at a time until smooth, 15–20 seconds each, then whisk in 2 tsp vanilla extract. Add the red liquid food coloring and whisk until the batter is evenly tinted, about 20 seconds.
Add the dry ingredients to the wet in three additions, alternating with the buttermilk (beginning and ending with dry). Whisk gently after each addition just until incorporated, about 1 minute total; do not overmix.
Quickly stir in the distilled white vinegar just until evenly dispersed; the batter may lightly foam, 5–10 seconds.
Divide the batter evenly between the prepared pans and smooth the tops. Bake until the centers spring back and a toothpick comes out with a few moist crumbs, 25–30 minutes.
Cool the cakes in the pans for 10 minutes, then turn out onto a wire rack, peel away parchment, and cool completely until no warmth remains, about 60 minutes.
Make the frosting: In a stand mixer or with a hand mixer, beat the softened cream cheese and softened unsalted butter on medium speed until smooth and fluffy, 2–3 minutes. Gradually beat in the powdered sugar on low, then increase to medium and beat until creamy, 2–3 minutes. Beat in the remaining 1 tsp vanilla extract until combined, 30 seconds.
Assemble: If needed, level the cooled cake layers. Place one layer on a serving plate and spread about 1.5–2 cups frosting evenly to the edges, 1–2 minutes. Set the second layer on top, apply a thin crumb coat over the top and sides, and chill to set, about 15 minutes. Finish with a final coat of frosting, smoothing as desired, 3–5 minutes. Slice and serve.