can't go wrong with steak! top it off with garlic mashed potatoes and cooked veggies [peppers, mushrooms, zucchini and onions, or whatever you like most] and a decadent dessert of your choice...baked brownies or a cute cake would be nice! remember, it's not all about him, it's about what you like too! i really hope he gets you a nice gift for being such a lovely gf...all the best
Just be with him and keep it simple... see what he does for you
Cook him something that is easy for you to make and something that he likes. If you are not good at cooking, then I would suggest a quiche because they are easy to make.
something that he likes, so if he is a steak man cook him steak, no point going all out on a dish that he has no interest in eating, it will annoy him, then you will get upset he did not like it even though you spent ages on it,
hope you two have a great day
lasagne, if he likes it.