Lemon sponge biscuit

  • 3 eggs
  • 125 grams (4.41 ounces) sugar
  • 100 grams (3.53 ounces) flour
  • 20 grams (0.71 ounces) vegetable oil
  • 20 grams (0.71 ounces) lemon juice
  • zest of 1 lemon

Poppy mousse

  • 7 grams (0.25 ounces) gelatin 220 bloom
  • 40 grams (1.41 ounces) water
  • 180 grams (6.35 ounces) milk
  • 180 grams (6.35 ounces) white chocolate
  • 300 grams (10.58 ounces) whipping cream
  • 30 grams (1.06 ounces) poppy seeds

Mirror glaze

  • 7 grams (0.25 ounces) gelatin 220 bloom
  • 40 grams (1.41 ounces) water for gelatin
  • 110 grams (3.88 ounces) glucose syrup
  • 55 grams (1.94 ounces) water
  • 110 grams (3.88 ounces) sugar
  • 110 grams (3.88 ounces) white chocolate
  • 75 grams (2.65 ounces) condensed milk
  • food colorant (to your preference)


  • Electric mixer

    Essential for whipping the eggs and sugar to achieve the perfect airy texture.

  • Silicone spatula

    Ideal for gently folding in ingredients without deflating the batter.

  • 18cm (7.09 inch) baking ring

    Perfect for shaping your cake layers evenly; don't forget to wrap it with film.

  • Side tape

    Keeps the sides of the cake neat and straight; highly recommended for a professional finish.

  • Paring knife and round cutters

    Useful for cutting out perfect cake circles.


Step 1

Whip the eggs with sugar on high speed for at least 8 minutes. This helps to incorporate air, making the sponge light and fluffy. Sift the flour in several stages and gently fold with a silicone spatula from the bottom up. Add the zest, food coloring, oil, and lemon juice, gently stirring with a spatula. Pour the batter onto a baking sheet (30x40 cm | 11.80x15.70 inch) lined with parchment paper, and bake at 320°F (160°C) for about 10 minutes. Cool the sponge, and cut out 3 circles with a diameter of 16 cm (6.30 inches).

Step 2

Soak the poppy seeds in hot milk for 1 hour. This will soften them and enhance their flavor. Soak the gelatin in cold water for 10 minutes. Afterward, bring the milk (from the soaked poppy seeds) back to a boil, then pour it over the white chocolate, stirring until the chocolate is completely dissolved. Add the melted gelatin to the chocolate mixture. Whip the cold cream to soft peaks. Fold a small portion of the cream into the chocolate mixture, then combine both mixtures.

Step 3

Wrap an 18 cm (7.09 inch) ring with film, and cover the sides with side tape. Lay out the first cake layer and spread part of the mousse, then add the second cake layer and some more mousse, and repeat. Place the assembled cake in the freezer overnight. Once frozen, drizzle the cake with the mirror glaze.

Step 4

Soak the gelatin in cold water. In a saucepan, mix the water, sugar, and glucose syrup. Heat the syrup to 217°F (103°C), then pour it over the white chocolate and condensed milk. Stir the mixture until the chocolate dissolves and add the dissolved gelatin. If necessary, add food colorant and blend the mixture with an immersion blender at a 45-degree angle. The ideal operating temperature for the glaze is 86-95°F (30-35°C).


This elegant pastry is a feast for both the eyes and the palate! 🌟 Serve it on a beautiful platter adorned with fresh lemon slices and mint leaves for that extra touch of sophistication. 🌿 Don't forget a side dollop of whipped cream or a scoop of vanilla ice cream🍦—these additions can elevate the dish to a whole new level!

For a more casual setting, you could slice the cake into petite, bite-sized pieces. It makes for a perfect high tea or coffee break treat ☕. Pair it with a fresh, hot cup of herbal tea or a chilled glass of lemonade for a refreshing contrast. 🍋

Looking to make a real statement? 😉 Add decorative edible gold leaf or dust a bit of powdered sugar on the top for that extra "wow" factor. Trust us, your guests will be snapping pics for Instagram in no time! 📸


Want to make this delightful treat gluten-free? Simply replace the regular flour with a reliable gluten-free flour blend. Ensure all other ingredients such as gelatin and white chocolate are certified gluten-free to avoid cross-contamination. 🌾

For a vegan version, you can substitute eggs with a flaxseed meal (1 tbsp flaxseed meal + 3 tbsp water per egg) and use agar-agar in place of gelatin. Opt for a high-quality dairy-free white chocolate and non-dairy whipping cream to maintain that creamy texture. 🥥

Adding these substitutions adds a unique twist while still preserving the essence of this exquisite dessert. So, go ahead and customize it to suit your dietary needs! 🌱✨


  • Why isn't my sponge cake rising properly?

    Ensure you are whipping the eggs and sugar at high speed for at least 8 minutes. This step incorporates enough air to help the sponge rise.

  • Can I use regular milk for the mousse instead of soaking poppy seeds?

    Soaking the poppy seeds in hot milk enhances the flavor and texture, but if you're in a pinch, you can use pre-soaked poppy seeds and regular milk. The results might slightly differ.

  • Why does my glaze not shine properly?

    Ensure you are working within the temperature range of 86-95F (30-35C) for optimal shine. Overheating can dull the glaze.

  • Should I use fresh or bottled lemon juice?

    Fresh lemon juice is highly recommended for a bright, tangy flavor. Bottled lemon juice can be used but might not offer the same zestiness.

  • Is there a substitute for glucose syrup?

    Yes, you can use light corn syrup as an alternative, although the consistency and taste might slightly differ.

  • Can I prepare the components in advance?

    Absolutely! You can make the sponge cake and mousse a day ahead. Assemble and freeze overnight, and apply the mirror glaze the next day for the best results.

Nutrition facts

Lemon & poppy mousse cake
Recipe Yield:1 cake
Calories:Calories per cake
Calories (Min - Max):3675 - 3750
Total Fat:230g
Saturated Fat:138g
Total Carbohydrate:340g
Total Sugars:215g