Preheat the oven to 350℉ and line a baking sheet with parchment paper. Set aside.
Place the cubed cornbread into a large bowl with the olive oil, salt, and pepper. Use your hands or a large spoon to gently toss the cornbread with the olive oil until evenly coated—the more you handle the cornbread, the more it will crumble.
Transfer the cornbread onto the prepared baking sheet and spread into an even layer. Bake in the oven for around 45 minutes, tossing and flipping the pieces every 10-15 minutes for even browning.
Once the croutons are evenly toasted and crisp on all sides, remove the pan from the oven and allow them to cool completely. Serve immediately or store in an airtight container for up to a week.