Line an 8x8-inch baking pan with parchment paper, leaving overhang on two sides like handles.
To the bowl of a food processor fitted with a steel blade, add the peanut butter, dates, and rolled oats. Pulse several times, until the mixture breaks down and the ingredients begin to incorporate with one another. Scrape down the bowl then add the chia seeds, protein powder, and 2 tablespoons milk. Pulse until all ingredients are well combined. Depending upon your food processor, this may take a few minutes.
Check the consistency of your dough. When you pick up a small handful of it and squeeze, it should hold together and resemble cookie dough. If it is too dry, continue pulsing in milk, 1 tablespoon at a time, until you reach the right consistency. Transfer the mixture to a mixing bowl. Add the chocolate chips and with a spatula (or your fingers), stir to combine the chips and moisten any bits of dough that the food processor didn't incorporate evenly.
Transfer mixture into the prepared pan and press it into an even, flat layer. Transfer the pan to the freezer for 15 minutes or the refrigerator for 1 hour, until the bars firm up.
Lift the bars from the pan using the parchment handles and transfer to a cutting board. Slice into bars of desired size and enjoy.
TO STORE: Store the bars in the refrigerator for up to 2 weeks. Due to their “no bake” consistency, the bars will become soft at room temperature.
TO FREEZE: Place the bars in an airtight freezer-safe storage container in the freezer for up to 3 months.