Melt 100g of unsalted butter in a microwave-safe bowl for about 30 seconds until creamy. Combine with 100g of white caster sugar and 75g of light brown sugar, mixing until smooth. Whisk in one whole egg, an egg yolk, and one teaspoon of vanilla extract until blended and creamy.

Incorporate 225g of self-raising flour and a pinch of salt into your wet mixture. Fold these dry ingredients until a soft dough starts to form. Add in 150g of chocolate chunks, mixing until evenly distributed.

Cover the mixing bowl with cling film and refrigerate for at least 5 hours or overnight to enhance flavors and prevent spreading.

Preheat your oven to 180°C (fan oven). Line a baking tray with parchment paper and roll chilled dough into balls, arranging 12 to 14 on the tray. Bake for 10 minutes until edges are golden but centers are soft.

Press a Mini Malteser Bunny and a Mini Egg onto each warm cookie. The heat will slightly melt the candy for a festive look.

Let cookies sit for 20 minutes to firm up before transferring to a wire rack to cool completely.