To cook, you’ve got two options:
Cut in half immediately to allow butter inside to spew out–kids always love that–but give the inside a few minutes to cool before letting our child eat it; the piece will require additional cutting to be handled by a child, which we like to do along the long side of the piece. Though it doesn’t need additional sauces or condiments, serving the dish the same way you would nuggies–i.e., with things in which to dunk the chicken–may make it more familiar or accessible to your kiddo.
Chicken Kiev is typically made with breast meat, but thighs are a more sensible portion size for a child. If you go with the latter, be sure to get boneless and skinless thighs with little or no fat on the pieces; remove any lingering bits of skin and/or fat before you prepare the chicken. Preparation is the same, but check the pieces at the eight minute mark of cooking, as they will likely need 2-3 less minutes to cook than breasts.