Sticky toffee celebration cake

Toffee Flavour Buttercream (32%) (Sugar, Butter (Milk), Glucose Syrup, Water, Invert Sugar Syrup, Colour (Caramel), Maize Starch, Flavouring, Preservative (Potassium Sorbate), Humectant (Glycerol), Emulsifier (E471), Dried Egg White)), Sugar, Wheat Flour (Wheat Flour, Calcium Carbonate, Iron, Niacin, Thiamin), Toffee Sauce (9%) (Sugar, Sweetened Condensed Milk (Whole Milk, Sugar), Double Cream (Milk), Butter (Milk), Glucose Syrup, Humectant (Sorbitol), Invert Sugar Syrup, Salt, Preservative (Potassium Sorbate)), Pasteurised Egg, Rapeseed Oil, Humectant (Glycerol), Cocoa Butter, Black Treacle, Dried Whole Milk, Maize Starch, Cocoa Mass, Caramelised Sugar Syrup, Raising Agents (E450, Sodium Hydrogen Carbonate), Flavouring, Coconut Oil, Emulsifiers (E481, E471, E472e, Soya Lecithin, E322), Glucose Syrup, Preservative (Potassium Sorbate), Salt, Milk Fat, Dried Whey (Milk), Lactose (Milk), Acidity Regulator (E330), Sweetened Condensed Milk (Whole Milk, Sugar), Dried Egg White, Palm Oil, Butter (Milk), Margarine (Palm Oil, Rapeseed Oil, Water, Flavouring, Vitamin A, Vitamin D), Invert Sugar Syrup