I agree with other posters who tell you that it's your party not MIL's. However, it might be best if you handle it carefully, otherwise your child's Grandma may not even come to the party. I am not kidding, some of these control freaks will go to any lengths to get their own way.
You don't want to start some major family rift over some food and drinks at a party. What I would do is just sort of smile and say "That's a good idea," and then do exactly what you want anyway. If MIL questions you about it the day of, just say "Oh, yea, we were supposed to get some pork chops, weren't we?" Or you could say that one of your son's friends at the party is Jewish and can't eat pork, so who can really argue with that one?? If she asks about alcohol, just tell her there was a small budget problem or something. Surely even she can understand that one coming from a young couple like yourselves with a new family?
After you handle things this way on one or two more occasions, MIL may just take the hint and figure out that her so-called "suggestions" are not wanted.
If you wanted to be really cheeky, you could always make the burgers and dogs for everyone else at the party, but to your MIL serve one perfectly grilled pork chop and a glass of wine. Just do this when she is in the kitchen and no one else notices. She will get the idea pretty damn quick! A wicked idea that would have Miss Manners scolding, perhaps, but honestly these folks can be just like so many overgrown kids! It is infuriating!
Whatever you decide to do, just don't let this difficult woman spoil your memory of your boy's very first birthday. It is so special. I know what this is like, because my daughter's baptism day turned into a nightmare from hell because of my Monster In Law and to this day, I can't think about it without being upset. Nothing is worth that.
Good luck,
SB
