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Select a crumbly cookie. Crush up your favorite cookies. Blend the cookie crumbs in a food processor. Add vegetable oil or butter. Sprinkle powdered sugar or sweetened condensed milk into the paste. Transfer the cookie butter into a lidded jar.
Part of the beauty of cookie butter is that you can make it with practically any kind of cookie. That being said, you should think about whether your favorite cookie is ideal for turning into a spreadable substance. You want a variety that crumbles into coarse granules easily, rather than a chewy recipe which will just get mushy or pasty when blended. For example, snickerdoodles, sugar cookies, pecan sandies, and oatmeal cookies all make great selections for cookie butter. Fig newtons, cream pies, and chewy or fudgy cookies are ill-advised. Once you've measured out eight ounces (227 g) of cookies from their package, lay them out on a cheesecloth, paper towel, or chopping board. Lay another cloth on top of them and then crush them into coarse chunks. You can use your hands, a potato masher, a meat tenderizer, or any other implement that's handy. If you've used a cookie with a filling, such as Nutter Butters or Oreos, scrape off the filling before crushing the crunchy wafers. Once your cookies look roughly the size of bread crumbs, you can dump them in your blender to grind them into a fine powder. Use the pulse function and make sure the blender lid is screwed on tightly to avoid a powdery mess in the kitchen. Depending on your personal preferences, you can use either cup vegetable oil (170 g) or stick (56 g) in your cookie butter. Just be sure to drizzle the oil in gradually, or if you're using butter, heat it up and melt it beforehand so that you spoon it in slowly. This will ensure that you distribute the butter or oil evenly throughout the crumbs. You want the finished product to look like a paste. Many cookbooks and food bloggers recommend using unsalted butter in your confections, but it's actually a matter of personal preference. Again, you can decide which ingredient you want to use depending on whether you prefer to bake with powdered sugar or condensed milk. Whichever one you use, measure out cup (170 g). If you're using sugar, scrape it off and down from the sides of the blender to make sure it gets into the mixture at the bottom rather than forming a residue on the walls. If your mixture still looks dry, add a little water until it reaches the desired consistency. If you're unsure, try dabbing a bit onto a cracker or piece of bread and see if it spreads easily. Using a spatula or large spoon, scrape all of your spread into a glass or plastic jar that can be closed tightly with a lid. Put it in the refrigerator for 30 minutes before serving. If you've got leftovers, no problem! Just pop your remaining cookie butter back in the fridge and keep it there for up to a week.