Start by lining a 9×9-inch or 9×13-inch baking dish with parchment paper. Any size works, but smaller dishes mean thicker bars.
In a high-speed food processor, combine dates, peanut butter, oat flour, honey, vanilla extract, and protein powder. Process until smooth, adding water as needed until you get a cookie dough-like consistency.
Transfer the dough into the prepared baking dish and press it evenly.
For the chocolate topping, melt dark chocolate chips and coconut oil together, then pour over the bars. Sprinkle with coarse sea salt.
Freeze the bars for 30 minutes to an hour until the chocolate sets.
Once set, slice and store in the fridge for up to 7 days or freeze for up to 3 months.