1. Shape the cake

    Make a buttercream icing by beating 150g softened butter in a bowl until smooth. Add 300g icing sugar and 2 tsp vanilla extract, then continue beating for 5 mins or until very pale and fluffy. Set aside. Make a heart-shaped template out of baking paper. Cut a rectangle (about 28 x 24cm), fold in half widthways and draw half a heart shape along the folded edge. Cut out and unfold. Cut 4 x 296g Madeira or chocolate loaf cakes into 4cm-thick slices and arrange in a single layer on a tray, sandwiching the pieces together with a little of the buttercream to form a shape the same size as the heart. Place the heart template over the top and use a small, sharp serrated knife to cut around the heart shape – you may need to trim the template to fit, or use small pieces from a fifth cake to fill in any gaps.

  2. Cover with buttercream

    Smooth the rest of the buttercream over the cake with a palette knife to completely cover the top and sides in a thin, smooth layer (you may not need all the icing, save any leftovers for icing cupcakes or offcuts from the cakes). 

  3. Cover with fondant

    Lightly dust the work surface with icing sugar. Roll out 500g white fondant icing in a thin layer to a rough circle, making sure it is large enough to cover the cake and sides. Dust the rolling pin with icing sugar and use it to help lift the icing over the cake. Smooth down the sides with your hands, pushing the icing around the heart shape. Use a small, sharp knife to trim the edges at the bottom of the cake. Try to get the icing as smooth as possible, as this and any bumps or cracks will show through the glaze (see tip below). Transfer the cake on the tray to the freezer and freeze for 8 hrs, or overnight, before glazing.

  4. Prepare the glaze

    Whisk a 12g sachet powdered gelatine into 80ml cold water until it starts to thicken. Set aside for 5 mins where it will thicken further. In a small pan, mix together 95ml water with 190g caster sugar and 125g condensed milk, then place over a gentle heat. Stir for a few mins until smooth and just heated through, then remove from the heat and stir in the gelatine mixture. Pour the mixture through a fine sieve over a bowl or jug and push through to remove any lumps of gelatine. Finely chop 220g white cooking chocolate.

  5. Finish the glaze

    Put the chocolate in a heatproof bowl. Pour over the warm gelatine mixture and leave for 10 mins for the chocolate to melt. Stir gently until completely smooth. Pour half the glaze into a separate bowl. Add 1 tsp strong red food colour gel to one bowl and a small dot of the gel to the other. Stir again to create a vibrant red-pink glaze and a pale pink glaze, adding more food colouring as needed. Set aside to thicken for a few mins, then give both bowls a sharp tap on the worktop to remove any air bubbles. The glaze should remain slightly warm to be able to be poured – if you have a sugar thermometer, you can check: the glaze should be between 32-34°C, or if not, it should be the consistency of thick double cream.

  6. Glaze the cake

    Set up a glazing station by placing a wire rack on a large lipped tray to catch any drips. Remove the solid cake from the freezer and place directly on the rack. Pour the darker glaze over the cake, ensuring it goes all over the top and down the sides of the cake. Pour or spoon over the paler glaze in swirls to create a marbled pattern – you can use a palette knife to help create more distinct swirls as you like. Leave to set for up to 1 hr at room temperature.

  7. Serve

    Use a large cake slice or similar to help transfer the cake to a serving plate or cake stand. To fully set, the cake should be left for a further 4-6 hrs at room temperature before serving. When ready to serve, dip a sharp knife into hot water before cutting for a clean slice. Serve small slices or squares with a few fresh berries, if you like.

    Tesco step by steps Valentine cake landscapeCalories 547 (27%), sugar 76g (84%), fat 19.6g (28%), saturates 12.2g (61%), salt 0.64g (11%), based on 24 servings. As part of a healthy balanced diet, we recommend this recipe for a special occasion or treat.

  8. Tips

    To get a smooth finish on the fondant icing, roll together any offcuts of icing and dust lightly with icing sugar. Use this as a pad to help buff out any imperfections in the icing, rubbing gently over the cake to help smooth it out.

    If the glaze seems too thick to pour over the cake, gently warm the mixture over a very low heat, stirring regularly, to loosen.

    If any air bubbles appear in the finished glaze on the cake, use a cocktail stick to gently pop them.

    Excess glaze that drips off the sides of the cake onto the tray can be poured into a bowl and stored in the fridge for up to 1 week for icing other cakes.

  9. Ingredients

    We’ve made a handy shopping list so you can get everything you need to make this beautiful mirror-glazed cake recipe. Don’t forget to screenshot before you go shopping!

    4-5 x 296g Madeira or chocolate loaf cakes
    For the icing:
    150g butter
    300g icing sugar, plus extra for dusting
    2 tsp vanilla extract
    500g white fondant icing
    For the glaze:
    12g sachet powdered gelatine
    175ml water
    190g caster sugar
    125g condensed milk
    220g white cooking chocolate
    extra strong red food colour gel
    fresh berries, to serve (optional)