Ingredients 1 cup wholemeal flour ½ teaspoon of salt ½ teaspoon of baking soda 100gr unsalted butter at room temperature ¾ cup brown sugar 1 egg 1 teaspoon vanilla extract 1 large or 2 small ripe banana 1 cup rolled oats 100gr of dark chocolate (drops or bar) ½ cup (170gr) of walnuts Preparation mode: If the butter is still in the refrigerator, take it out and leave it at room temperature. Heat the oven to 200ºc. Separate two large baking sheets and line with parchment paper. In a bowl, mix together the dry ones - whole flour, salt and baking soda - and set aside.On a plate, mash the banana well with a fork, set aside. With a knife, chop the nuts into small pieces. If using chocolate bars, chop into small pieces as well. Book everything. In an electric mixer, beat the butter with the brown sugar, until it is well mixed, fluffy and with a lighter color. Add the egg and vanilla. Add the mashed banana and beat some more. Finally add the dry mix and beat very slowly, just until the flour is incorporated, do not beat too much. Turn off the mixer and, using a spatula, add the oats, nuts and chocolate. Mix well. Now decide whether you want big or small cookies, or both. For the big ones, use a scoop of ice cream (or a tablespoon), ideal to keep them very round. For the little ones, a full teaspoon will do just fine. Distribute the dough balls on the baking sheets and refrigerate for at least 20 minutes. Take it to the oven, straight from the fridge, and bake the cookies until they get darker, changing the baking sheets in the middle of cooking. Small ones take about 15 minutes and large ones take about 20 minutes. Remove from the oven and let it cool completely. Store in a tightly closed container. If after a while they get a little shriveled, just roast them again, for about 10 minutes in the oven preheated to 180ºc.