Preheat air fryer to 375 F. Heat rice according to package directions.

In large mixing bowl, combine rice, diced onions, cumin and Mexican cheese blend. Mix well.

Add beaten egg to rice mixture and stir until fully combined.

Using hands, shape about 2 tablespoons rice mixture into ball. Repeat with remaining mixture.

Roll rice balls in breadcrumbs, ensuring they are fully coated.

Lightly coat air fryer basket with nonstick cooking spray to prevent sticking.

Place rice bites in single layer in air fryer basket, leaving space between each for even cooking. Work in batches, if necessary. Spray tops of each ball with nonstick cooking spray to help with browning.

Cook 15 minutes, or until golden brown and crisp, flipping halfway through for even browning.

Allow to cool slightly and serve with salsa or sour cream, if desired.