I've made variations of this recipe over the years, sometimes i replace some of the flour with quick cook oats, used
Preheat oven to 190C
1 Tablespoon Cocoa
¼ Teaspoon Baking Powder
¼ Teaspoon Bicarbonate of Soda
½ Teaspoon Salt
125g butter Unsalted Butter, softened. In a pinch it's fine to use good quality Margarine (For the love of god, please don't use hydrogenated fats!)
75g Soft Light Brown Sugar
½ Teaspoon Vanilla Extract
1 Large Egg
½ Cup Chocolate Chips (or good quality dark chocolate chopped into small chunks)
Cool on baking sheet for 5 minutes then carefully remove to cooling racks.
Pour yourself a huge glass of cold milk and..
N.B. I needed a couple of tries with this recipe. The size you'll want the cookies to be actually makes a difference, and I've taken a pic before to show you my various attempts:
Top left: Those were made with 100 grams of flour and 75 of hazelnut meal. They are lovely - crispy on the outside and gooey on the inside. The problem was that I used around a tablespoon of mixture and they spread and flattened so much they joined together.
Top right: The exact same mixture, but i used less. They taste fine, but they spread really, really thin and the only part that's not thin is where the choc chips are.
Bottom: I added some more flour to these, and they turned out great. They have the right amount of bite, chunky cookies that are softer on the inside, and crispy on the outside.