Pink lemon cake (birthday cake for the best friend)

Name: Pink lemon cake (birthday cake for the best friend)
Cook time: 2 h 45 min
Total time: 2 h 45 min
Yield: 16
Ingredients: 475 g Icing sugar; 1 Protein (size M); 7-10 Tbsp food colouring in different colours; 1 untreated lemon; 275 g soft butter; 350 g Sugar; 7-10 Tbsp Salt; 5 Eggs (size M); 275 g Flour; 2 1/2 TSP. Baking Powder; 200 ml Milk; 4 TABLESPOONS Lemon-Curd; 700 g Marzipan raw mass; baking paper; 7-10 Tbsp Paper; 7-10 Tbsp Birthday candles