Chocolate Obsession Traybake
A Mary Berry inspired chocolate obsession traybake cake recipe. Full of dark chocolate and topped with a silky chocolate icing, every mouthful is moist and a pure chocolatey delight.

Rachel's Recipe Pantry contains affiliate links and is a member of the Amazon Services LLC Associates Program. If you make a purchase using one of these Amazon links, we may receive compensation at no extra cost to you. See our Disclosure Policy for more information.
Ingredients
Chocolate Sponge
- 350 g Dark Chocolate (Broken into pieces)
- 225 g Margarine (or butter softened)
- 3 Eggs (Beaten)
- 400 g Caster Sugar
- 400 g Self-Raising Flour (Sifted)
- 1½ tsp Baking Powder
- 300 ml Water
Ganache Icing - 225 g Dark Chocolate (Broken into pieces)
- 125 ml Double Cream (or Creme Fraiche)
How To Make Chocolate Obsession Traybake
Preheat the oven to 160℃/140℃fan/Gas 3/320℉. Line a large roasting tin with baking paper, making sure there is some overhang around the edges for easy removal.
Chocolate Obsession Sponge
- Add the chocolate pieces, butter and water to a saucepan and heat gently over low heat, stirring until melted and smooth. Cool slightly.
- Add the beaten eggs to a bowl with the sugar and beat until smooth. Gradually pour in the chocolate mixture and whisk until smooth. Add the sifted flour and the baking powder and mix until smooth.
- Pour into the roasting tin and spread evenly. Bake in the oven for 30-35 minutes. Leave in the tin for ten minutes before lifting out onto a wire rack. Leave to cool completely.
Ganache
- Gently heat the cream in a pan and add the chocolate pieces. Stir until melted forming that chocolate obsession icing.
- Pour over the traybake and spread evenly with a palette knife. Set aside until firm then cut into rectangular pieces to serve.

How Do You Store A Chocolate Traybake
With the baking paper intact transfer to a flat rectangular storage box. Alternatively cut into pieces and store in air tight containers. It will keep for up to 5 days.
Can You Freeze Chocolate Obsession Cake?
Yes, this chocolate obsession cake freezes well but not iced.
Prepare Ahead
The cake can be made the day ahead and kept in the fridge but best to ice with the ganache on the day of serving.
If you love this recipe you may also like:
Quick Chocolate Éclair Cake Made With Puff Pastry
Easy Date and Pecan Traybake (Mary Berry Inspired)
Light And Soft Ginger Traybake Cake
Best Ever Chocolate Fudge Traybake

Chocolate Obsession Traybake
Equipment
Ingredients
Chocolate Sponge
- 350 g Dark Chocolate (Broken into pieces)
- 225 g Margarine (or butter softened)
- 3 Eggs (Beaten)
- 400 g Caster Sugar
- 400 g Self-Raising Flour (Sifted)
- 1½ tsp Baking Powder
- 300 ml Water
Ganache Icing
- 225 g Dark Chocolate (Broken into pieces)
- 125 ml Double Cream (or Creme Fraiche)
Instructions
- Preheat the oven to 160℃/140℃fan/Gas 3/320℉. Line a large roasting tin with baking paper, making sure there is some overhang around the edges for easy removal.
Chocolate Sponge
- Add the chocolate pieces, butter and water to a saucepan and heat gently over low heat, stirring until melted and smooth. Cool slightly.
- Add the beaten eggs to a bowl with the sugar and beat until smooth. Gradually pour in the chocolate mixture and whisk until smooth. Add the sifted flour and the baking powder and mix until smooth.
- Pour into the roasting tin and spread evenly. Bake in the oven for 30-35 minutes. Leave in the tin for ten minutes before lifting out onto a wire rack. Leave to cool completely.
Ganache
- Gently heat the cream in a pan and add the chocolate pieces. Stir until melted.
- Pour over the traybake and spread evenly with a palette knife. Set aside until firm then cut into rectangular pieces to serve.
Haven’t tried yet but want to. If I use a 9″ square tin, would that work without adjustments? Many thanks for posting.
Hi Jayne, it depends how deep it is. If you find it’s getting too full use a small tin for the leftover, such as a 1 lb loaf tin. Note the smaller tin will take less time to bake. Ideally if you want to go down this route bake the smaller tin first then the larger tin after. Hope that helps 😉