best 4th of july red, white and blue velvet cake

Ingredients

• 5 cups all-purpose flour (spoon and sweep)
• 4 teaspoons baking powder
• 1 1/2 teaspoons salt
• 2 cups milk
• 2 teaspoons vanilla extract
• 3 1/4 cups sugar
• 2 cups vegetable oil
• 6 large egg whites
• 2 teaspoons white vinegar
• - red and blue food coloring
• 3 packages packages cream cheese
• 1 1/2 cups 3 sticks) unsalted butter, softened
• 12 cups 3-pounds) confectioners' sugar
• 1 tablespoon vanilla extract
• - red food coloring
• - blue decorating sugar