Preheat the Oven: Set your oven to 375°F (190°C). Line a large baking sheet with parchment paper for easy cleanup; set aside.
Prepare the Bread: Place the bread cubes in a large mixing bowl. Drizzle the olive oil evenly over the cubes, ensuring they’re lightly coated. Sprinkle Italian seasoning, garlic powder, salt, and black pepper evenly over the bread. Toss gently using a large spoon or your hands until all cubes are uniformly coated.
Arrange on the Baking Sheet: Spread the seasoned bread cubes in a single layer on the prepared baking sheet. Ensure they are spaced apart to promote even browning.
Bake: Place the baking sheet in the oven and bake for 10-15 minutes, turning the croutons halfway through to brown all sides evenly. Keep a close eye on them during the last few minutes to avoid over-toasting. If necessary, extend the baking time in 1-2 minute intervals for desired crispness. Since all ovens vary, be sure to check doneness often, you can always bake more, but you cannot "unbake".
Cool and Store: Remove the baking sheet from the oven and let the croutons cool completely. Once cooled, use them immediately or transfer them to an airtight container for storage. Homemade croutons stay fresh for up to 1 week when stored in a cool, dry place.