HI, I agree with other moms about letting him tell you when he is finished. If he is not wanting that bottle afterwards, can you give it to him later so he is still getting those nutrients he needs in formula? Or, give him the bottle first? Anyway, I like one of the suggestions about feeding him certain table foods that he could have. On that, I have two great articles that may interest you either now or for when he is a toddler and eating mostly table food. The first one is for parents of a picky toddler, and even though he does not seem picky, it has some fun ideas. The second is about great/fun ways to introduce healthy foods and help your child learn about health and nutrition so they make healthy choices on their own later on.
http://www.askdrsears.com/html/3/T030800.asp "Feeding Toddlers: 17 Tips for Pleasing the Picky Eater" .
and
http://www.askdrsears.com/html/4/T040200.asp "ABC's of Teaching Nutrition to Kids" The article talks about referring to "grow" foods for kids.
Also, a great book to read is "If It's Not Food, Don't Eat It" by Kelly Hayford, C.N.C. It is really interesting and tells how to make healthy choices for your family. This would be important as your son grows and is eating what you eat. I loved reading it.
Best wishes!