Line an 8-inch square pan with parchment paper, leaving some overhanging paper on the sides. Set aside.
In the bowl of a food processor, add the peanut butter, dates, almond milk and vanilla extract. Blend until the mixture is smooth and consistent, about 1 minute.
Stop the food processor to scrape down the sides, then add the oats, protein powder, ground flaxseed and salt. Pulse a few times until the ingredients are well combined. The mixture should have a cookie dough-like texture. If it’s too dry, add a splash of milk. If it’s too wet, add more protein powder and pulse again.
Transfer the mixture to a mixing bowl and fold in the chocolate chips with a rubber spatula or your hands.
Press the mixture into the prepared pan and flatten out the top with your hands or the back of a spoon. It helps to spray your hands with oil when pressing down. Place in the freezer until it sets, about 15 minutes.
Use the overhanging parchment paper to lift from the baking pan, and slice into 8 bars. Enjoy immediately.