Preheat oven to 350°F (175°C) and grease a 9-inch springform pan.
Whisk flour, sugar, and cocoa powder in a bowl.
Mix oil, buttermilk, eggs, vinegar, and red food coloring in a separate large bowl until smooth.
Combine wet and dry ingredients gently, pour into the pan, and bake for 25-30 minutes.
Cool the cake completely in the pan on a wire rack.
Puree strawberries in a blender until smooth.
Beat softened cream cheese and powdered sugar until creamy, then mix in the puree.
Whip heavy cream to stiff peaks in a cold bowl, then fold gently into the strawberry mixture.
Spread filling over the cooled cake and refrigerate for at least 4 hours.