Line a 9x13-inch baking dish with parchment paper.

Combine oats, flaxseed meal, raisins, cranberries, and protein powder in a small bowl.

Place chocolate chips, honey, and peanut butter in a microwave-safe bowl. Microwave until chocolate chips are nearly melted, 2 to 3 minutes, stirring every 30 seconds.

Combine oats mixture and chocolate mixture until evenly mixed; spread into the prepared baking dish.

Refrigerate bars until hardened, 15 to 20 minutes. Remove bars from dish by lifting parchment; cut into squares using a pizza cutter.