01 - Preheat oven to 350°F (175°C). Line a rimmed baking sheet (approximately 10x15 inches) with parchment paper or foil and lightly grease it.
02 - Arrange saltine crackers in a single layer to cover the entire base of the prepared baking sheet.
03 - In a saucepan over medium heat, melt the butter and brown sugar. Stir constantly until the mixture begins to boil. Continue boiling for 3 minutes, stirring frequently. Remove from heat and stir in the vanilla extract and a pinch of salt.
04 - Immediately pour the hot toffee mixture evenly over the saltine crackers. Spread gently with a spatula to ensure all crackers are coated.
05 - Bake in the preheated oven for 8–10 minutes, or until the toffee is bubbling and the crackers have absorbed some of the caramel.
06 - Remove the baking sheet from the oven. Sprinkle chocolate chips evenly over the hot toffee. Allow to sit for 2 minutes until softened, then use an offset spatula to spread the melted chocolate into an even layer.
07 - In a microwave-safe bowl, melt the white chocolate chips in 20-second intervals, stirring between each interval until smooth. Stir in the cherry gelatin powder and add vegetable oil, 1 teaspoon at a time, until a drizzling consistency is achieved.
08 - Using a spoon or a piping bag, drizzle the cherry-flavored white chocolate over the still-warm chocolate layer.
09 - If desired, sprinkle the bark with chopped dried cherries, nuts, and flaky sea salt.
10 - Allow the bark to cool completely at room temperature for about 30 minutes, or refrigerate to expedite the process. Once set, break or cut the bark into desired pieces.