Collect together your equipment (see Recipe Notes below) and ingredients.

Preheat oven to Fan Oven 160°C/180°C/350°F/Gas 4

Put the butter, salt and both of the sugars into a large bowl and, using an electric whisk, mix until fluffy. This should take 3-4 minutes. You may need to scrape down the sides of the bowl to ensure it mixes evenly.

Scrape down the sides of the bowl with a spatula and add the egg and vanilla extract. Beat again with an electric whisk until thoroughly mixed.

Add the flour and baking powder to the butter mixture. Either beat with an electric whisk on the slowest speed (to avoid a cloud of flour covering your kitchen!) or mix in with a wooden spoon.

Chop the eggs – I like quite large chunks so I just halve them. It is a bit fiddly and I find that the easiest way, is to do one at a time. Alternatively, pulse in a food processor until you get the required size. You will find you get a mix of sizes doing it this way.

Add to the mixing bowl and fold through the chocolate chunks.

Now transfer to your cake tin – you can use round or square tins:

- 2 x Round 15cm/6in greased and lined cake tin – divide the cookie dough between the 2 tins and and level the surface. Add extra mini eggs and cook in the centre of a preheated oven for 20 – 25 minutes. OR

- Round 23cm/9in greased and lined cake tin – use all the cookie dough and level the surface. Add extra mini eggs and cook in the centre of a preheated oven for 25 – 30 minutes. OR

- Square 20cm/8in greased and lined cake tin – use all the cookie dough and level the surface. Add extra mini eggs and cook in the centre of a preheated oven for 25 – 30 minutes.

Leave in the tin for around 30 minutes to cool.

Lift out of the tin and transfer to a cooling rack. Slice when cool.