Preheat oven to 180c or 350F
Melt the butter in the microwave for 30 seconds, then let it cool
Add the sugars and whisk until just combined
Add the egg yolk and vanilla and mix until just combined
Add the rest of the dry ingredients and using a spatula, mix until a cookie dough forms
Chop the chocolate (reserve some for the top) and mix the raspberries with 1/2 tsp of flour and mix into the cookie dough batter
Scoop 12 Cookies onto a baking tray and top with the rest of the chocolate (no need to chill)
Bake for 8-10 minutes (I take mine out of the oven on the 9 minute mark)
Let it cool in the pan for 10-15 minutes