1. Melt the butter and let cool down a bit. Add together with both sugars to a large bowl and mix until light and fluffy – takes about 2-3 minutes. Add the egg and vanilla extract and mix well. Mix the flour with cocoa powder, baking soda, and salt and add together with the milk to the bowl – mix until just combined. Add the chocolate covered raisins and rolled oats to the bowl and fold in. Place the dough in the fridge for about 30 minutes.

2. Preheat the oven to 360°F (180°C). Line a baking sheet with baking parchment. Use a cookie scoop or two tablespoons and place dough portions with some space in between on the baking sheet. Bake for 10 minutes, take out of the oven, and “smash” the cookies with the back of a spoon to flatten them. Return the baking sheet to the oven and bake the cookies for 2-3 minutes longer. The cookies will still be quite soft. Take out of the oven and let cool down on the baking sheet for about 10 minutes, then transfer to a wire rack and let cool down completely. Repeat with the remaining dough.