Preheat the oven to 400 degrees F.
Pour oil into a small baking dish. Season the turkey tenderloins with salt and place in the baking dish. Arrange the carrots all around the turkey and turn to coat with oil. Place the onions over the carrots in the pan.
In a small bowl, combine the chicken broth and sage. Pour the mixture over the turkey.
Roast the turkey and vegetables for 40 minutes, until an instant-read thermometer registers 160 degrees F in the thickest part of the tenderloin. Let the turkey rest for 10 minutes before slicing crosswise into 1/2-inch thick slices.
For baby's portion, transfer turkey and vegetables to a food processor or blender and puree, thinning with reserved pan juices as necessary, to desired consistency.