I find that my girlfriend and I have completely different tastes in the food we eat. She is essentially a pescatarian and I will eat just about anything. I am extremely adventurous with my meals and she tends to stick to what she knows. When I prepare dinner I attempt to incorporate items that she is familiar with while adding a twist to the norm for her. While I can't just throw together something brand new to her, I can however introduce her palate to new tastes for future meals. I cook a lot and I like to add bold flavors to my food. I have traveled around the world a bit and have the opportunity to try a variety of multi-cultural foods.
The slow introduction to new flavor profiles is very beneficial to making meals when you have to be wary of your partner's likes and dislikes. To this day, I have yet to make a meal that she has not enjoyed and I have opened her palate up to new items, including shellfish, pork, and beef. The key to everything in short, is slow change, with a reassurance that what is being made will have great flavor and and consistent textures.