Cut 70g of butter into small pieces and place them in a bowl. Heat using a double boiler or microwave on low heat, checking every 15-20 seconds until the butter is completely melted into a liquid.

Put the Melted butter into a bowl and add 50g of powdered sugar. Stir well until the butter and sugar are fully blended. This step will help create a crisp texture for the cookies.

Crack 1 egg into the bowl and continue to mix until the egg is fully incorporated with the butter and sugar, forming a smooth batter.

Sift 120g of low-gluten flour, 5g of baking powder, and 12g of cocoa powder into the batter. Use a spatula to roughly mix the flour into the batter until it forms a crumbly texture, then knead the dough with your hands until smooth. Be careful not to over-knead the dough, as this can affect the texture of the cookies.

Divide the dough into 25g portions and roll each into a ball. Place the balls on a baking tray, ensuring there is enough space between them as they will spread out during baking.

Gently press down on each ball with your fingers to flatten them into even round discs. The ideal thickness is about 1 - 1.5 cm. If the cookies are too thick, they won’t bake properly; if too thin, they may burn.

Preheat the oven to 170°C. Place the baking tray with the cookies in the middle of the oven and bake for 15 - 18 minutes. Keep an eye on the cookies as they bake; when the edges start to brown and the surface feels firm when pressed, they are done. Remove from the oven and let the cookies cool on the tray for a few minutes.

While the cookies are cooling, chop the white chocolate into small pieces and melt it over a pot of hot water (double boiler method). Once melted, transfer the white chocolate into a piping bag. Place the candy eyes on top to make the mummy look. Pipe irregular lines of chocolate over the cookies to simulate the bandages of a mummy. Your adorable mummy cocoa cookies are now ready!