Chocolate cake with buttercream icing

Buttercream icing (powdered sugar [sugar, cornstarch], vegetable shortening [palm oil, soybean oil, cottonseed oil, monoglycerides, polysorbate 60], nonfat dry milk, dried egg whites, natural and artificial flavor, salt), sugar, enriched wheat flour (bleached wheat flour, niacin, reduced iron, thiamine mononitrate, riboflavin, folic acid), chocolate cake concentrate (bleached wheat flour, cocoa powder [processed with alkali], nonfat dry milk, palm oil, modified food starch [corn], sugar, potassium bicarbonate, dextrose, sodium acid pyrophosphate, salt, <span class="allergen">soy lecithin</span>, soybean oil, <span class="allergen">whey</span>, gums [cellulose, guar, xanthan], sodium stearoyl lactylate, cornstarch, natural and artificial flavors, monocalcium phosphate, cinnamon), <span class="allergen">eggs</span>, soybean oil, <span class="allergen">butter</span>, <span class="allergen">egg whites</span> (<span class="allergen">egg whites</span>, guar gum, triethyl citrate), <span class="allergen">soy lecithin</span>, emulsifier (water, mono - and diglycerides, sugar).