Method:

1. Cream the butter, two sugars, salt, bicarbonate soda together slowly with the paddle attachment in an electric stand mixer. Alternatively you can use a handheld beater.
2. Continue until the mix is pale and smooth. Use a small spatula to scrape the insides of the bowl to ensure it has mixed evenly.
3. Add the egg and continue to beat on a low to medium speed, mix well before again scraping down the sides.
4. Add the flour and the two chocolate and mix slowly until it is all incorporated.
5. Add the frozen chunks of raspberry and mix again, use lightly floured hands to weigh 8 even sized pieces of dough. They will each weigh around 85g. 
6. Roll these into balls and reserve on a tray and refrigerate (or freeze).
7. Preheat the oven to 180°C and place cookie balls onto a baking tray lined with paper. (Suggestion: no more than 4 cookies at a time on a standard baking tray.)
8. Bake for 18-20 minutes or until golden brown.
9. Remove from the oven. Press each cookie down gently with a weight such as the base of a saucepan, don’t squash completely, just gently flatten.
10. Finish each cooked cookie by placing dark & milk chocolate onto the surface of each hot cookie. Add a few raspberries on top.
11. Place the cookies back into the oven for 30 seconds to melt. 
12. Remove the cookies and allow to cool on the tray for two minutes before using a metal slice or palette knife to lift each cookie onto a wire rack. 
13. If freezing the dough: Once the balls are frozen, you can transfer them to a ziplock bag or container and store them in the freezer for up to 1 month. These can then be baked as needed (from frozen) ensuring you always have a fresh cookie to hand.