Pat frozen edamame dry with paper towels to remove excess moisture and achieve maximum crispiness.

Preheat oven to 400°F (200°C) and line a baking sheet with parchment paper.

Toss dried edamame with olive oil in a medium bowl until evenly coated.

Mix sea salt, garlic powder, black pepper, and red pepper flakes in a small bowl.

Sprinkle seasoning mixture over oiled edamame and toss to coat evenly.

Spread seasoned edamame in a single layer on prepared baking sheet without crowding.

Roast in preheated oven for 15-20 minutes, stirring halfway through, until golden brown and crispy.

If using Parmesan cheese, sprinkle over hot roasted edamame immediately after removing from oven.

Cool for 2-3 minutes before serving. Beans will continue to crisp up as they cool.

Transfer to serving bowl and enjoy immediately for best texture. Store leftovers in an airtight container for up to 3 days.