Gather all ingredients. Preheat the oven to 350 degrees F (175 degrees C).

Combine garlic powder, seasoned salt, onion powder, dried oregano, salt, and pepper in a small bowl.

Pour 1/3 first beer can into the bottom of a 9x13-inch baking dish. Place open beer can in the center of the baking dish.

Rinse chicken under cold running water. Discard giblets and neck from chicken; drain and pat dry. Fit whole chicken over open beer can with the legs on the bottom.

Cut a small slit on each side of chicken breasts using a paring knife. Press the tip of each wing into the slit to encourage even cooking.

Rub reserved garlic seasoning mixture over chicken.

Pat green onion slices evenly onto chicken. Press green onion halves into top of chicken cavity. Pour 1/2 second beer can into the pan.

Bake chicken in the preheated oven for 45 minutes. Pour remaining beer into the pan under chicken: bake until no longer pink at the bone and the juices run clear, about 30 additional minutes. An instant-read thermometer inserted into the thickest part of the thigh, near the bone, should read 180 degrees F (82 degrees C).

Discard beer can. Cover chicken with a doubled sheet of aluminum foil.

Let rest for 10 minutes before slicing.