Berry Delicious Cake

Name: Berry Delicious Cake
Prep time: 2 h
Cook time: 30 min
Total time: 2 h 30 min
Cuisine: World Cuisine, American
Ingredients: 2 cups + 2 tablespoons all-purpose flour*; 1 teaspoon baking powder; 1 teaspoon baking soda; 1 teaspoon salt; 1 cup any type of vegetable oil, including non-virgin olive oil or avocado oil; 2 large eggs; 2 cups Imperial Sugar Extra Fine Granulated Sugar; 1 cup buttermilk; 1 tablespoon vanilla extract; 1/2 cup hot water; 2 teaspoons white distilled vinegar; 2/3 cup strawberry fruit spread; 2/3 cup blueberry or blackberry fruit spread; Basic buttercream frosting; 1 cup (2 sticks) unsalted butter, super soft; 1 cup Imperial Sugar Extra Fine Granulated Sugar; Pinch salt; 3/4 cup evaporated milk, room temperature; 1 teaspoon vanilla extract; 2 cups frozen blackberries (do not use fresh); 4 tablespoons Imperial Sugar Extra Fine Granulated Sugar; 1 tablespoon lemon juice; 1 tablespoon cornstarch; 1 tablespoon water; 1 pint fresh blackberries (optional)