3 cups (375 g) all-purpose flour, plus more for dusting
1 cup (240 ml) vegetable oil
1 1⁄2 cups (338 g) dark brown sugar
1 cup (117 g) chopped walnuts
4 large eggs, at room temperature
1⁄2 cup (120 ml) sour cream, room temperature
1 tbsp (15 ml) pure vanilla extract
2 1⁄2 tsp (11 g) baking powder
1 1⁄2 tsp + 1 tsp baking soda
1 1/2 tsp ground cinnamon
1 tsp sea salt
Vegetable oil spray, for pans
Place the chopped dates and water into a small saucepan over medium heat. Simmer until the dates have softened. Add the 1 tsp baking soda and mix with a fork until smooth. The mixture will increase in volume after adding the baking soda and will become bubbly. Set aside until the mixture has reached room temperature.
Preheat the oven to 350°F (176°C). Spray with vegetable oil spray, dust with flour and line four 6-inch round cake pans with parchment paper.
In a large bowl, whisk together the oil, brown sugar, walnuts, eggs, sour cream, vanilla, and date mixture until well combined, then set aside.
Sift together the flour, baking powder, baking soda, ground cinnamon and salt into the bowl of your stand mixer that has been fitted with the paddle attachment.
Set your mixer to a low speed and slowly pour in the wet ingredients. Increase the mixer speed to medium and beat until smooth, no longer than 1 minute. Be sure not to over-beat the batter, as it may cause the cakes to deflate while baking.
Divide the cake batter equally among the prepared pans. Bake for 30 to
35 minutes, or until a toothpick inserted into the center of a cake comes out clean and the cake has pulled away from the edges slightly. Remove from
the oven and allow the cakes to cool in their pans for approximately 15 minutes before inverting onto wire racks or a clean countertop. Allow the layers to cool completely before filling and decorating.
Fill and frost with caramel Italian meringue buttercream and add a caramel drip if desired.