To start, grab the bowl of your stand mixer fitted with the paddle attachment. If you don’t have one, a large mixing bowl and electric mixer will do. Combine ½ cup unsalted butter, ¾ cup light brown sugar, 1 large egg, and 2 teaspoons vanilla extract. Beat these ingredients on medium-high speed for about 4 minutes. You want everything to be well creamed and combined, creating a lovely light mixture.
Once your mixture is nice and fluffy, stop to scrape down the sides of the bowl. Next, add in 1 ¼ cups all-purpose flour, ½ cup old-fashioned oats, 1 teaspoon cornstarch, ½ teaspoon baking soda, and a pinch of salt. Beat on low speed until everything is just combined, which should take about 1 minute. Don’t overmix here!
After that, again scrape down the sides of the bowl to ensure everything is mixed evenly. Now, it’s time to fold in the fun stuff. Add 4.25 ounces of diced protein bars, ¾ cup dried cranberries, ½ cup pumpkin seeds, and ¼ cup raisins. Beat on low speed until all the ingredients are combined, which should only take about 30 seconds.
Now comes the fun part! Using a large cookie scoop, a ¼-cup measure, or even your hands, form approximately 12 equal-sized mounds of dough. Roll them into balls and slightly flatten them. A little tip here: strategically place some of the dried fruit or protein bar pieces on top of each mound for that extra flair.
Once your dough is shaped, place the mounds on a large plate or tray. Cover them with plastic wrap and refrigerate for at least 2 hours or up to 5 days. This step is crucial because baking with unchilled dough can lead to thinner, flatter cookies that spread too much.
When you’re ready to bake, preheat your oven to 350°F (about 175°C). Line a baking sheet with a Silpat or spray it with cooking spray to prevent sticking. Place your cookie dough mounds on the sheet, making sure they’re spaced at least 2 inches apart. I usually bake about 8 cookies per sheet for the best results.
Now, pop those cookies in the oven and bake for about 11 minutes. You’re looking for the edges to be set while the tops remain slightly undercooked and glossy in the center. Remember, they will firm up as they cool, so don’t overbake!
Once baked, allow your cookies to cool on the baking sheet for about 10 minutes before serving. I recommend letting them cool on the sheet rather than transferring to a rack, as it helps them maintain their structure better.
These Trail Mix Protein Bar Cookies will keep well in an airtight container at room temperature for up to 1 week. If you want to make them ahead of time, you can also freeze them for up to 6 months. Alternatively, unbaked dough can be stored in the refrigerator for up to 5 days, or in the freezer for up to 4 months, making it easy to bake them fresh whenever you're in the mood.